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* [PATCH v2 0/6] Implement heap guard feature
@ 2017-10-17 13:29 Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 1/6] MdeModulePkg/DxeCore: Implement heap guard feature for UEFI Jian J Wang
                   ` (5 more replies)
  0 siblings, 6 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel
  Cc: Star Zeng, Eric Dong, Jiewen Yao, Michael Kinney, Ayellet Wolman

> Patch V2 changes:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message 
> c. Fix malfunction in 32-bit boot mode
> d. Add comment for the use of mOnGuarding
> e. Change name of function InitializePageTableLib to 
>    InitializePageTableGlobals
> f. Add code in 32-bit code to bypass setting page table to read-only
> g. Coding style clean-up
>

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is disabled by default and is not recommended to enable it
in production build of BIOS.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Ayellet Wolman <ayellet.wolman@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>

Jian J Wang (6):
  MdeModulePkg/DxeCore: Implement heap guard feature for UEFI
  MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  MdeModulePkg/MdeModulePkg.dec,.uni: Add heap guard related PCDs and
    string tokens
  UefiCpuPkg/CpuDxe: Reduce debug message
  UefiCpuPkg/PiSmmCpuDxeSmm: Disable page table protection
  MdeModulePkg/DxeIpl: Enable paging for heap guard

 MdeModulePkg/Core/Dxe/DxeMain.inf               |    4 +
 MdeModulePkg/Core/Dxe/Mem/HeapGuard.c           | 1184 +++++++++++++++++++
 MdeModulePkg/Core/Dxe/Mem/HeapGuard.h           |  380 ++++++
 MdeModulePkg/Core/Dxe/Mem/Imem.h                |   38 +-
 MdeModulePkg/Core/Dxe/Mem/Page.c                |  129 +-
 MdeModulePkg/Core/Dxe/Mem/Pool.c                |  154 ++-
 MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf         |    1 +
 MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c |   29 +-
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c    | 1446 +++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h    |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c    |  704 +++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h    |  174 +++
 MdeModulePkg/Core/PiSmmCore/Page.c              |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c         |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h         |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf       |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c              |   75 +-
 MdeModulePkg/MdeModulePkg.dec                   |   57 +
 MdeModulePkg/MdeModulePkg.uni                   |   58 +
 UefiCpuPkg/CpuDxe/CpuPageTable.c                |    5 +-
 UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c        |    7 +
 UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf    |    1 +
 UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c         |    3 +-
 23 files changed, 4904 insertions(+), 96 deletions(-)
 create mode 100644 MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/Dxe/Mem/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

-- 
2.14.1.windows.1



^ permalink raw reply	[flat|nested] 13+ messages in thread

* [PATCH v2 1/6] MdeModulePkg/DxeCore: Implement heap guard feature for UEFI
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode Jian J Wang
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Star Zeng, Eric Dong, Jiewen Yao, Michael Kinney

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Add comment for the use of mOnGuarding
> c. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message 
>
> Other changes:
> d. Fix issues in 32-bit boot mode
> e. Remove prototype of empty functions
>

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT0 and BIT1 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiBootServicesData
and EfiRuntimeServicesData by setting the PCD with value 0x50.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Note: Turning on heap guard, especially pool guard, will introduce too many
memory fragments. Windows 10 has a limitation in its boot loader, which
accepts at most 512 memory descriptors passed from BIOS. This will prevent
Windows 10 from booting if heap guard is enabled. The latest Linux
distribution with grub boot loader has no such issue. Normally it's not
recommended to enable this feature in production build of BIOS.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 MdeModulePkg/Core/Dxe/DxeMain.inf     |    4 +
 MdeModulePkg/Core/Dxe/Mem/HeapGuard.c | 1184 +++++++++++++++++++++++++++++++++
 MdeModulePkg/Core/Dxe/Mem/HeapGuard.h |  380 +++++++++++
 MdeModulePkg/Core/Dxe/Mem/Imem.h      |   38 +-
 MdeModulePkg/Core/Dxe/Mem/Page.c      |  129 +++-
 MdeModulePkg/Core/Dxe/Mem/Pool.c      |  154 ++++-
 6 files changed, 1825 insertions(+), 64 deletions(-)
 create mode 100644 MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/Dxe/Mem/HeapGuard.h

diff --git a/MdeModulePkg/Core/Dxe/DxeMain.inf b/MdeModulePkg/Core/Dxe/DxeMain.inf
index e29d6c83ae..6b27714a79 100644
--- a/MdeModulePkg/Core/Dxe/DxeMain.inf
+++ b/MdeModulePkg/Core/Dxe/DxeMain.inf
@@ -56,6 +56,7 @@
   Mem/MemData.c
   Mem/Imem.h
   Mem/MemoryProfileRecord.c
+  Mem/HeapGuard.c
   FwVolBlock/FwVolBlock.c
   FwVolBlock/FwVolBlock.h
   FwVol/FwVolWrite.c
@@ -192,6 +193,9 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdPropertiesTableEnable                   ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdImageProtectionPolicy                   ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy             ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask                   ## CONSUMES
 
 # [Hob]
 # RESOURCE_DESCRIPTOR   ## CONSUMES
diff --git a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
new file mode 100644
index 0000000000..49f6d3c62b
--- /dev/null
+++ b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
@@ -0,0 +1,1184 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "DxeMain.h"
+#include "Imem.h"
+#include "HeapGuard.h"
+
+//
+// Global to avoid infinite reentrance of memory allocation when updating
+// page table attributes, which may need allocate pages for new PDE/PTE.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding = FALSE;
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+  EFI_STATUS              Status;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      Status = CoreInternalAllocatePages (
+                  AllocateAnyPages,
+                  EfiBootServicesData,
+                  EFI_SIZE_TO_PAGES (Size),
+                  &MapMemory,
+                  FALSE
+                  );
+      ASSERT_EFI_ERROR (Status);
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      Status = CoreInternalAllocatePages (
+                  AllocateAnyPages,
+                  EfiBootServicesData,
+                  EFI_SIZE_TO_PAGES (Size),
+                  &MapMemory,
+                  FALSE
+                  );
+      ASSERT_EFI_ERROR (Status);
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  //
+  // Set flag to make sure allocating memory without GUARD for page table
+  // operation; otherwise infinite loops could be caused.
+  //
+  mOnGuarding = TRUE;
+  gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  mOnGuarding = FALSE;
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  //
+  // Set flag to make sure allocating memory without GUARD for page table
+  // operation; otherwise infinite loops could be caused.
+  //
+  mOnGuarding = TRUE;
+  gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, 0);
+  mOnGuarding = FALSE;
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+  BOOLEAN     InSmm;
+
+  if (gCpu == NULL || AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  InSmm = FALSE;
+  if (gSmmBase2 != NULL) {
+    gSmmBase2->InSmm (gSmmBase2, &InSmm);
+  }
+
+  if (InSmm) {
+    return FALSE;
+  }
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0) {
+    return FALSE;
+  }
+
+  if (PageOrPool == GUARD_HEAP_TYPE_POOL) {
+    ConfigBit = PcdGet64 (PcdHeapGuardPoolType);
+  } else if (PageOrPool == GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit = PcdGet64 (PcdHeapGuardPageType);
+  } else {
+    ConfigBit = (UINT64)-1;
+  }
+
+  if ((UINT32)MemoryType >= MEMORY_TYPE_OS_RESERVED_MIN) {
+    TestBit = BIT63;
+  } else if ((UINT32) MemoryType >= MEMORY_TYPE_OEM_RESERVED_MIN) {
+    TestBit = BIT62;
+  } else if (MemoryType < EfiMaxMemoryType) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Allocate or free guarded memory
+
+  @param[in]  Start           Start address of memory to allocate or free
+  @param[in]  NumberOfPages   Memory size in pages
+  @param[in]  NewType         Memory type to convert to
+
+  @return VOID
+**/
+EFI_STATUS
+CoreConvertPagesWithGuard (
+  IN UINT64           Start,
+  IN UINTN            NumberOfPages,
+  IN EFI_MEMORY_TYPE  NewType
+  )
+{
+  if (NewType == EfiConventionalMemory) {
+    AdjustMemoryF (&Start, &NumberOfPages);
+  } else {
+    AdjustMemoryA (&Start, &NumberOfPages);
+  }
+
+  return CoreConvertPages(Start, NumberOfPages, NewType);
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
diff --git a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h
new file mode 100644
index 0000000000..ed7fe7a371
--- /dev/null
+++ b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h
@@ -0,0 +1,380 @@
+/** @file
+  Data type, macros and function prototypes of heap guard feature.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT0
+#define GUARD_HEAP_TYPE_PAGE        BIT1
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+EFI_STATUS
+CoreConvertPages (
+  IN UINT64           Start,
+  IN UINT64           NumberOfPages,
+  IN EFI_MEMORY_TYPE  NewType
+  );
+
+/**
+  Allocate or free guarded memory
+
+  @param[in]  Start           Start address of memory to allocate or free
+  @param[in]  NumberOfPages   Memory size in pages
+  @param[in]  NewType         Memory type to convert to
+
+  @return VOID
+**/
+EFI_STATUS
+CoreConvertPagesWithGuard (
+  IN UINT64           Start,
+  IN UINTN            NumberOfPages,
+  IN EFI_MEMORY_TYPE  NewType
+  );
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/Dxe/Mem/Imem.h b/MdeModulePkg/Core/Dxe/Mem/Imem.h
index fb53f95575..e58a5d62ba 100644
--- a/MdeModulePkg/Core/Dxe/Mem/Imem.h
+++ b/MdeModulePkg/Core/Dxe/Mem/Imem.h
@@ -1,7 +1,7 @@
 /** @file
   Data structure and functions to allocate and free memory space.
 
-Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
@@ -61,6 +61,7 @@ typedef struct {
   @param  PoolType               The type of memory for the new pool pages
   @param  NumberOfPages          No of pages to allocate
   @param  Alignment              Bits to align.
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocated memory, or NULL
 
@@ -69,7 +70,8 @@ VOID *
 CoreAllocatePoolPages (
   IN EFI_MEMORY_TYPE    PoolType,
   IN UINTN              NumberOfPages,
-  IN UINTN              Alignment
+  IN UINTN              Alignment,
+  IN BOOLEAN            NeedGuard
   );
 
 
@@ -95,6 +97,7 @@ CoreFreePoolPages (
 
   @param  PoolType               Type of pool to allocate
   @param  Size                   The amount of pool to allocate
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocate pool, or NULL
 
@@ -102,7 +105,8 @@ CoreFreePoolPages (
 VOID *
 CoreAllocatePoolI (
   IN EFI_MEMORY_TYPE  PoolType,
-  IN UINTN            Size
+  IN UINTN            Size,
+  IN BOOLEAN          NeedGuard
   );
 
 
@@ -145,6 +149,34 @@ CoreReleaseMemoryLock (
   VOID
   );
 
+/**
+  Allocates pages from the memory map.
+
+  @param  Type                   The type of allocation to perform
+  @param  MemoryType             The type of memory to turn the allocated pages
+                                 into
+  @param  NumberOfPages          The number of pages to allocate
+  @param  Memory                 A pointer to receive the base allocated memory
+                                 address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
+
+  @return Status. On success, Memory is filled in with the base address allocated
+  @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in
+                                 spec.
+  @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
+  @retval EFI_OUT_OF_RESOURCES   No enough pages to allocate.
+  @retval EFI_SUCCESS            Pages successfully allocated.
+
+**/
+EFI_STATUS
+EFIAPI
+CoreInternalAllocatePages (
+  IN EFI_ALLOCATE_TYPE      Type,
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN UINTN                  NumberOfPages,
+  IN OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN BOOLEAN                NeedGuard
+  );
 
 //
 // Internal Global data
diff --git a/MdeModulePkg/Core/Dxe/Mem/Page.c b/MdeModulePkg/Core/Dxe/Mem/Page.c
index 3dd6d1b4a0..648b21d429 100644
--- a/MdeModulePkg/Core/Dxe/Mem/Page.c
+++ b/MdeModulePkg/Core/Dxe/Mem/Page.c
@@ -14,6 +14,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
 #include "DxeMain.h"
 #include "Imem.h"
+#include "HeapGuard.h"
 
 //
 // Entry for tracking the memory regions for each memory type to coalesce similar memory types
@@ -285,9 +286,12 @@ AllocateMemoryMapEntry (
     //
     // The list is empty, to allocate one page to refuel the list
     //
-    FreeDescriptorEntries = CoreAllocatePoolPages (EfiBootServicesData,
+    FreeDescriptorEntries = CoreAllocatePoolPages (
+                              EfiBootServicesData,
                               EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION_GRANULARITY),
-                              DEFAULT_PAGE_ALLOCATION_GRANULARITY);
+                              DEFAULT_PAGE_ALLOCATION_GRANULARITY,
+                              FALSE
+                              );
     if (FreeDescriptorEntries != NULL) {
       //
       // Enque the free memmory map entries into the list
@@ -894,17 +898,41 @@ CoreConvertPagesEx (
     //
     CoreAddRange (MemType, Start, RangeEnd, Attribute);
     if (ChangingType && (MemType == EfiConventionalMemory)) {
-      //
-      // Avoid calling DEBUG_CLEAR_MEMORY() for an address of 0 because this
-      // macro will ASSERT() if address is 0.  Instead, CoreAddRange() guarantees
-      // that the page starting at address 0 is always filled with zeros.
-      //
       if (Start == 0) {
+        //
+        // Avoid calling DEBUG_CLEAR_MEMORY() for an address of 0 because this
+        // macro will ASSERT() if address is 0.  Instead, CoreAddRange()
+        // guarantees that the page starting at address 0 is always filled
+        // with zeros.
+        //
         if (RangeEnd > EFI_PAGE_SIZE) {
           DEBUG_CLEAR_MEMORY ((VOID *)(UINTN) EFI_PAGE_SIZE, (UINTN) (RangeEnd - EFI_PAGE_SIZE + 1));
         }
       } else {
-        DEBUG_CLEAR_MEMORY ((VOID *)(UINTN) Start, (UINTN) (RangeEnd - Start + 1));
+        //
+        // If Heap Guard is enabled, the page at the top and/or bottom of
+        // this memory block to free might be inaccessible. Skipping them
+        // to avoid page fault exception.
+        //
+        UINT64  StartToClear;
+        UINT64  EndToClear;
+
+        StartToClear = Start;
+        EndToClear   = RangeEnd;
+        if (PcdGet8 (PcdHeapGuardPropertyMask) & (BIT1|BIT0)) {
+          if (IsGuardPage(StartToClear)) {
+            StartToClear += EFI_PAGE_SIZE;
+          }
+          if (IsGuardPage (EndToClear)) {
+            EndToClear -= EFI_PAGE_SIZE;
+          }
+          ASSERT (EndToClear > StartToClear);
+        }
+
+        DEBUG_CLEAR_MEMORY(
+          (VOID *)(UINTN)StartToClear,
+          (UINTN)(EndToClear - StartToClear + 1)
+          );
       }
     }
 
@@ -991,6 +1019,7 @@ CoreUpdateMemoryAttributes (
   @param  NewType                The type of memory the range is going to be
                                  turned into
   @param  Alignment              Bits to align with
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The base address of the range, or 0 if the range was not found
 
@@ -1001,7 +1030,8 @@ CoreFindFreePagesI (
   IN UINT64           MinAddress,
   IN UINT64           NumberOfPages,
   IN EFI_MEMORY_TYPE  NewType,
-  IN UINTN            Alignment
+  IN UINTN            Alignment,
+  IN BOOLEAN          NeedGuard
   )
 {
   UINT64          NumberOfBytes;
@@ -1093,6 +1123,17 @@ CoreFindFreePagesI (
       // If this is the best match so far remember it
       //
       if (DescEnd > Target) {
+        if (NeedGuard) {
+          DescEnd = AdjustMemoryS (
+                      DescEnd + 1 - DescNumberOfBytes,
+                      DescNumberOfBytes,
+                      NumberOfBytes
+                      );
+          if (DescEnd == 0) {
+            continue;
+          }
+        }
+
         Target = DescEnd;
       }
     }
@@ -1123,6 +1164,7 @@ CoreFindFreePagesI (
   @param  NewType                The type of memory the range is going to be
                                  turned into
   @param  Alignment              Bits to align with
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The base address of the range, or 0 if the range was not found.
 
@@ -1132,7 +1174,8 @@ FindFreePages (
     IN UINT64           MaxAddress,
     IN UINT64           NoPages,
     IN EFI_MEMORY_TYPE  NewType,
-    IN UINTN            Alignment
+    IN UINTN            Alignment,
+    IN BOOLEAN          NeedGuard
     )
 {
   UINT64   Start;
@@ -1146,7 +1189,8 @@ FindFreePages (
               mMemoryTypeStatistics[NewType].BaseAddress, 
               NoPages, 
               NewType, 
-              Alignment
+              Alignment,
+              NeedGuard
               );
     if (Start != 0) {
       return Start;
@@ -1157,7 +1201,8 @@ FindFreePages (
   // Attempt to find free pages in the default allocation bin
   //
   if (MaxAddress >= mDefaultMaximumAddress) {
-    Start = CoreFindFreePagesI (mDefaultMaximumAddress, 0, NoPages, NewType, Alignment);
+    Start = CoreFindFreePagesI (mDefaultMaximumAddress, 0, NoPages, NewType,
+                                Alignment, NeedGuard);
     if (Start != 0) {
       if (Start < mDefaultBaseAddress) {
         mDefaultBaseAddress = Start;
@@ -1172,7 +1217,8 @@ FindFreePages (
   // address range.  If this allocation fails, then there are not enough 
   // resources anywhere to satisfy the request.
   //
-  Start = CoreFindFreePagesI (MaxAddress, 0, NoPages, NewType, Alignment);
+  Start = CoreFindFreePagesI (MaxAddress, 0, NoPages, NewType, Alignment,
+                              NeedGuard);
   if (Start != 0) {
     return Start;
   }
@@ -1187,7 +1233,7 @@ FindFreePages (
   //
   // If any memory resources were promoted, then re-attempt the allocation
   //
-  return FindFreePages (MaxAddress, NoPages, NewType, Alignment);
+  return FindFreePages (MaxAddress, NoPages, NewType, Alignment, NeedGuard);
 }
 
 
@@ -1200,6 +1246,7 @@ FindFreePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return Status. On success, Memory is filled in with the base address allocated
   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in
@@ -1215,7 +1262,8 @@ CoreInternalAllocatePages (
   IN EFI_ALLOCATE_TYPE      Type,
   IN EFI_MEMORY_TYPE        MemoryType,
   IN UINTN                  NumberOfPages,
-  IN OUT EFI_PHYSICAL_ADDRESS  *Memory
+  IN OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN BOOLEAN                NeedGuard
   )
 {
   EFI_STATUS      Status;
@@ -1301,7 +1349,8 @@ CoreInternalAllocatePages (
   // If not a specific address, then find an address to allocate
   //
   if (Type != AllocateAddress) {
-    Start = FindFreePages (MaxAddress, NumberOfPages, MemoryType, Alignment);
+    Start = FindFreePages (MaxAddress, NumberOfPages, MemoryType, Alignment,
+                           NeedGuard);
     if (Start == 0) {
       Status = EFI_OUT_OF_RESOURCES;
       goto Done;
@@ -1311,12 +1360,19 @@ CoreInternalAllocatePages (
   //
   // Convert pages from FreeMemory to the requested type
   //
-  Status = CoreConvertPages (Start, NumberOfPages, MemoryType);
+  if (NeedGuard) {
+    Status = CoreConvertPagesWithGuard(Start, NumberOfPages, MemoryType);
+  } else {
+    Status = CoreConvertPages(Start, NumberOfPages, MemoryType);
+  }
 
 Done:
   CoreReleaseMemoryLock ();
 
   if (!EFI_ERROR (Status)) {
+    if (NeedGuard) {
+      SetGuardForMemory (Start, NumberOfPages);
+    }
     *Memory = Start;
   }
 
@@ -1351,8 +1407,11 @@ CoreAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;
 
-  Status = CoreInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type) && !mOnGuarding;
+  Status = CoreInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                      NeedGuard);
   if (!EFI_ERROR (Status)) {
     CoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -1393,6 +1452,7 @@ CoreInternalFreePages (
   LIST_ENTRY      *Link;
   MEMORY_MAP      *Entry;
   UINTN           Alignment;
+  BOOLEAN         IsGuarded;
 
   //
   // Free the range
@@ -1438,14 +1498,20 @@ CoreInternalFreePages (
     *MemoryType = Entry->Type;
   }
 
-  Status = CoreConvertPages (Memory, NumberOfPages, EfiConventionalMemory);
-
-  if (EFI_ERROR (Status)) {
-    goto Done;
+  IsGuarded = IsPageTypeToGuard (Entry->Type, AllocateAnyPages) &&
+              IsMemoryGuarded (Memory);
+  if (IsGuarded) {
+    Status = CoreConvertPagesWithGuard (Memory, NumberOfPages,
+                                        EfiConventionalMemory);
+  } else {
+    Status = CoreConvertPages (Memory, NumberOfPages, EfiConventionalMemory);
   }
 
 Done:
   CoreReleaseMemoryLock ();
+  if (IsGuarded) {
+    UnsetGuardForMemory(Memory, NumberOfPages);
+  }
   return Status;
 }
 
@@ -1843,6 +1909,12 @@ Done:
 
   *MemoryMapSize = BufferSize;
 
+  DEBUG_CODE (
+    if (PcdGet8 (PcdHeapGuardPropertyMask) & (BIT1|BIT0)) {
+      DumpGuardedMemoryBitmap ();
+    }
+  );
+
   return Status;
 }
 
@@ -1854,6 +1926,7 @@ Done:
   @param  PoolType               The type of memory for the new pool pages
   @param  NumberOfPages          No of pages to allocate
   @param  Alignment              Bits to align.
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocated memory, or NULL
 
@@ -1862,7 +1935,8 @@ VOID *
 CoreAllocatePoolPages (
   IN EFI_MEMORY_TYPE    PoolType,
   IN UINTN              NumberOfPages,
-  IN UINTN              Alignment
+  IN UINTN              Alignment,
+  IN BOOLEAN            NeedGuard
   )
 {
   UINT64            Start;
@@ -1870,7 +1944,8 @@ CoreAllocatePoolPages (
   //
   // Find the pages to convert
   //
-  Start = FindFreePages (MAX_ADDRESS, NumberOfPages, PoolType, Alignment);
+  Start = FindFreePages (MAX_ADDRESS, NumberOfPages, PoolType, Alignment,
+                         NeedGuard);
 
   //
   // Convert it to boot services data
@@ -1878,7 +1953,11 @@ CoreAllocatePoolPages (
   if (Start == 0) {
     DEBUG ((DEBUG_ERROR | DEBUG_PAGE, "AllocatePoolPages: failed to allocate %d pages\n", (UINT32)NumberOfPages));
   } else {
-    CoreConvertPages (Start, NumberOfPages, PoolType);
+    if (NeedGuard) {
+      CoreConvertPagesWithGuard (Start, NumberOfPages, PoolType);
+    } else {
+      CoreConvertPages (Start, NumberOfPages, PoolType);
+    }
   }
 
   return (VOID *)(UINTN) Start;
diff --git a/MdeModulePkg/Core/Dxe/Mem/Pool.c b/MdeModulePkg/Core/Dxe/Mem/Pool.c
index dd165fea75..b82b51595c 100644
--- a/MdeModulePkg/Core/Dxe/Mem/Pool.c
+++ b/MdeModulePkg/Core/Dxe/Mem/Pool.c
@@ -14,6 +14,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
 #include "DxeMain.h"
 #include "Imem.h"
+#include "HeapGuard.h"
 
 STATIC EFI_LOCK mPoolMemoryLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_NOTIFY);
 
@@ -169,7 +170,7 @@ LookupPoolHead (
       }
     }
 
-    Pool = CoreAllocatePoolI (EfiBootServicesData, sizeof (POOL));
+    Pool = CoreAllocatePoolI (EfiBootServicesData, sizeof (POOL), FALSE);
     if (Pool == NULL) {
       return NULL;
     }
@@ -214,7 +215,8 @@ CoreInternalAllocatePool (
   OUT VOID            **Buffer
   )
 {
-  EFI_STATUS    Status;
+  EFI_STATUS            Status;
+  BOOLEAN               NeedGuard;
 
   //
   // If it's not a valid type, fail it
@@ -238,6 +240,8 @@ CoreInternalAllocatePool (
     return EFI_OUT_OF_RESOURCES;
   }
 
+  NeedGuard = IsPoolTypeToGuard (PoolType) && !mOnGuarding;
+
   //
   // Acquire the memory lock and make the allocation
   //
@@ -246,7 +250,7 @@ CoreInternalAllocatePool (
     return EFI_OUT_OF_RESOURCES;
   }
 
-  *Buffer = CoreAllocatePoolI (PoolType, Size);
+  *Buffer = CoreAllocatePoolI (PoolType, Size, NeedGuard);
   CoreReleaseLock (&mPoolMemoryLock);
   return (*Buffer != NULL) ? EFI_SUCCESS : EFI_OUT_OF_RESOURCES;
 }
@@ -298,6 +302,7 @@ CoreAllocatePool (
   @param  PoolType               The type of memory for the new pool pages
   @param  NoPages                No of pages to allocate
   @param  Granularity            Bits to align.
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocated memory, or NULL
 
@@ -307,7 +312,8 @@ VOID *
 CoreAllocatePoolPagesI (
   IN EFI_MEMORY_TYPE    PoolType,
   IN UINTN              NoPages,
-  IN UINTN              Granularity
+  IN UINTN              Granularity,
+  IN BOOLEAN            NeedGuard
   )
 {
   VOID        *Buffer;
@@ -318,11 +324,14 @@ CoreAllocatePoolPagesI (
     return NULL;
   }
 
-  Buffer = CoreAllocatePoolPages (PoolType, NoPages, Granularity);
+  Buffer = CoreAllocatePoolPages (PoolType, NoPages, Granularity, NeedGuard);
   CoreReleaseMemoryLock ();
 
   if (Buffer != NULL) {
-    ApplyMemoryProtectionPolicy (EfiConventionalMemory, PoolType,
+    if (NeedGuard) {
+      SetGuardForMemory ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer, NoPages);
+    }
+    ApplyMemoryProtectionPolicy(EfiConventionalMemory, PoolType,
       (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer, EFI_PAGES_TO_SIZE (NoPages));
   }
   return Buffer;
@@ -334,6 +343,7 @@ CoreAllocatePoolPagesI (
 
   @param  PoolType               Type of pool to allocate
   @param  Size                   The amount of pool to allocate
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocate pool, or NULL
 
@@ -341,7 +351,8 @@ CoreAllocatePoolPagesI (
 VOID *
 CoreAllocatePoolI (
   IN EFI_MEMORY_TYPE  PoolType,
-  IN UINTN            Size
+  IN UINTN            Size,
+  IN BOOLEAN          NeedGuard
   )
 {
   POOL        *Pool;
@@ -355,6 +366,7 @@ CoreAllocatePoolI (
   UINTN       Offset, MaxOffset;
   UINTN       NoPages;
   UINTN       Granularity;
+  BOOLEAN     HasPoolTail;
 
   ASSERT_LOCKED (&mPoolMemoryLock);
 
@@ -372,6 +384,9 @@ CoreAllocatePoolI (
   // Adjust the size by the pool header & tail overhead
   //
 
+  HasPoolTail  = !(NeedGuard &&
+                   ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjusting the Size to be of proper alignment so that
   // we don't get an unaligned access fault later when
@@ -391,10 +406,16 @@ CoreAllocatePoolI (
   // If allocation is over max size, just allocate pages for the request
   // (slow)
   //
-  if (Index >= SIZE_TO_LIST (Granularity)) {
-    NoPages = EFI_SIZE_TO_PAGES(Size) + EFI_SIZE_TO_PAGES (Granularity) - 1;
+  if (Index >= SIZE_TO_LIST (Granularity) || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+    NoPages = EFI_SIZE_TO_PAGES (Size) + EFI_SIZE_TO_PAGES (Granularity) - 1;
     NoPages &= ~(UINTN)(EFI_SIZE_TO_PAGES (Granularity) - 1);
-    Head = CoreAllocatePoolPagesI (PoolType, NoPages, Granularity);
+    Head = CoreAllocatePoolPagesI (PoolType, NoPages, Granularity, NeedGuard);
+    if (NeedGuard) {
+      Head = AdjustPoolHeadA ((EFI_PHYSICAL_ADDRESS)(UINTN)Head, NoPages, Size);
+    }
     goto Done;
   }
 
@@ -422,7 +443,8 @@ CoreAllocatePoolI (
     //
     // Get another page
     //
-    NewPage = CoreAllocatePoolPagesI (PoolType, EFI_SIZE_TO_PAGES (Granularity), Granularity);
+    NewPage = CoreAllocatePoolPagesI (PoolType, EFI_SIZE_TO_PAGES (Granularity),
+                                      Granularity, NeedGuard);
     if (NewPage == NULL) {
       goto Done;
     }
@@ -468,30 +490,39 @@ Done:
 
   if (Head != NULL) {
 
+    //
+    // Account the allocation
+    //
+    Pool->Used += Size;
+
     //
     // If we have a pool buffer, fill in the header & tail info
     //
     Head->Signature = POOL_HEAD_SIGNATURE;
     Head->Size      = Size;
     Head->Type      = (EFI_MEMORY_TYPE) PoolType;
-    Tail            = HEAD_TO_TAIL (Head);
-    Tail->Signature = POOL_TAIL_SIGNATURE;
-    Tail->Size      = Size;
     Buffer          = Head->Data;
-    DEBUG_CLEAR_MEMORY (Buffer, Size - POOL_OVERHEAD);
+
+    if (HasPoolTail) {
+      Tail            = HEAD_TO_TAIL (Head);
+      Tail->Signature = POOL_TAIL_SIGNATURE;
+      Tail->Size      = Size;
+
+      Size -= POOL_OVERHEAD;
+    } else {
+      Size -= SIZE_OF_POOL_HEAD;
+    }
+
+    DEBUG_CLEAR_MEMORY (Buffer, Size);
 
     DEBUG ((
       DEBUG_POOL,
       "AllocatePoolI: Type %x, Addr %p (len %lx) %,ld\n", PoolType,
       Buffer,
-      (UINT64)(Size - POOL_OVERHEAD),
+      (UINT64)Size,
       (UINT64) Pool->Used
       ));
 
-    //
-    // Account the allocation
-    //
-    Pool->Used += Size;
 
   } else {
     DEBUG ((DEBUG_ERROR | DEBUG_POOL, "AllocatePool: failed to allocate %ld bytes\n", (UINT64) Size));
@@ -588,6 +619,34 @@ CoreFreePoolPagesI (
     (EFI_PHYSICAL_ADDRESS)(UINTN)Memory, EFI_PAGES_TO_SIZE (NoPages));
 }
 
+/**
+  Internal function.  Frees guarded pool pages.
+
+  @param  PoolType               The type of memory for the pool pages
+  @param  Memory                 The base address to free
+  @param  NoPages                The number of pages to free
+
+**/
+STATIC
+VOID
+CoreFreePoolPagesWithGuard (
+  IN EFI_MEMORY_TYPE        PoolType,
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NoPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryGuarded;
+  UINTN                   NoPagesGuarded;
+
+  MemoryGuarded  = Memory;
+  NoPagesGuarded = NoPages;
+
+  AdjustMemoryF (&Memory, &NoPages);
+  CoreFreePoolPagesI (PoolType, Memory, NoPages);
+
+  UnsetGuardForMemory (MemoryGuarded, NoPagesGuarded);
+}
+
 /**
   Internal function to free a pool entry.
   Caller must have the memory lock held
@@ -616,6 +675,8 @@ CoreFreePoolI (
   UINTN       Offset;
   BOOLEAN     AllFree;
   UINTN       Granularity;
+  BOOLEAN     IsGuarded;
+  BOOLEAN     HasPoolTail;
 
   ASSERT(Buffer != NULL);
   //
@@ -628,24 +689,32 @@ CoreFreePoolI (
     return EFI_INVALID_PARAMETER;
   }
 
-  Tail = HEAD_TO_TAIL (Head);
-  ASSERT(Tail != NULL);
+  IsGuarded   = IsPoolTypeToGuard (Head->Type) &&
+                IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Head);
+  HasPoolTail = !(IsGuarded &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
 
-  //
-  // Debug
-  //
-  ASSERT (Tail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (Head->Size == Tail->Size);
-  ASSERT_LOCKED (&mPoolMemoryLock);
+  if (HasPoolTail) {
+    Tail = HEAD_TO_TAIL (Head);
+    ASSERT (Tail != NULL);
 
-  if (Tail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
-  }
+    //
+    // Debug
+    //
+    ASSERT (Tail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (Head->Size == Tail->Size);
 
-  if (Head->Size != Tail->Size) {
-    return EFI_INVALID_PARAMETER;
+    if (Tail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (Head->Size != Tail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }
 
+  ASSERT_LOCKED (&mPoolMemoryLock);
+
   //
   // Determine the pool type and account for it
   //
@@ -680,14 +749,27 @@ CoreFreePoolI (
   //
   // If it's not on the list, it must be pool pages
   //
-  if (Index >= SIZE_TO_LIST (Granularity)) {
+  if (Index >= SIZE_TO_LIST (Granularity) || IsGuarded) {
 
     //
     // Return the memory pages back to free memory
     //
-    NoPages = EFI_SIZE_TO_PAGES(Size) + EFI_SIZE_TO_PAGES (Granularity) - 1;
+    NoPages = EFI_SIZE_TO_PAGES (Size) + EFI_SIZE_TO_PAGES (Granularity) - 1;
     NoPages &= ~(UINTN)(EFI_SIZE_TO_PAGES (Granularity) - 1);
-    CoreFreePoolPagesI (Pool->MemoryType, (EFI_PHYSICAL_ADDRESS) (UINTN) Head, NoPages);
+    if (IsGuarded) {
+      Head = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)Head);
+      CoreFreePoolPagesWithGuard (
+        Pool->MemoryType,
+        (EFI_PHYSICAL_ADDRESS)(UINTN)Head,
+        NoPages
+        );
+    } else {
+      CoreFreePoolPagesI (
+        Pool->MemoryType,
+        (EFI_PHYSICAL_ADDRESS)(UINTN)Head,
+        NoPages
+        );
+    }
 
   } else {
 
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 1/6] MdeModulePkg/DxeCore: Implement heap guard feature for UEFI Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  2017-10-18  5:07   ` Yao, Jiewen
  2017-10-17 13:29 ` [PATCH v2 3/6] MdeModulePkg/MdeModulePkg.dec, .uni: Add heap guard related PCDs and string tokens Jian J Wang
                   ` (3 subsequent siblings)
  5 siblings, 1 reply; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Star Zeng, Eric Dong, Jiewen Yao, Michael Kinney

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to 
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not
 
   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );
 
 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not
 
   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not
 
   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }
 
 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;
 
-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }
 
@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;
 
-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();
 
+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-  
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>
 
 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"
 
 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );
 
 /**
@@ -356,6 +359,8 @@ SmmFreePages (
 
   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not
 
   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );
 
 /**
@@ -1231,4 +1237,74 @@ typedef enum {
 
 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];
 
+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c
 
 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib
 
 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES
 
 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES
 
 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;
 
   Address = 0;
 
@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }
 
+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }
 
+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;
 
   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }
 
+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }
 
-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }
 
-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }
 
   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v2 3/6] MdeModulePkg/MdeModulePkg.dec, .uni: Add heap guard related PCDs and string tokens
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 1/6] MdeModulePkg/DxeCore: Implement heap guard feature for UEFI Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 4/6] UefiCpuPkg/CpuDxe: Reduce debug message Jian J Wang
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Star Zeng, Eric Dong, Jiewen Yao

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 MdeModulePkg/MdeModulePkg.dec | 57 ++++++++++++++++++++++++++++++++++++++++++
 MdeModulePkg/MdeModulePkg.uni | 58 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 115 insertions(+)

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index a3c0633ee1..99f5d88627 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -867,6 +867,63 @@
   # @ValidList  0x80000006 | 0x03058002
   gEfiMdeModulePkgTokenSpaceGuid.PcdErrorCodeSetVariable|0x03058002|UINT32|0x30001040
 
+  ## Indicates which type allocation need guard page.
+  # Below is bit mask for this PCD: (Order is same as UEFI spec)<BR>
+  #  EfiReservedMemoryType             0x0000000000000001<BR>
+  #  EfiLoaderCode                     0x0000000000000002<BR>
+  #  EfiLoaderData                     0x0000000000000004<BR>
+  #  EfiBootServicesCode               0x0000000000000008<BR>
+  #  EfiBootServicesData               0x0000000000000010<BR>
+  #  EfiRuntimeServicesCode            0x0000000000000020<BR>
+  #  EfiRuntimeServicesData            0x0000000000000040<BR>
+  #  EfiConventionalMemory             0x0000000000000080<BR>
+  #  EfiUnusableMemory                 0x0000000000000100<BR>
+  #  EfiACPIReclaimMemory              0x0000000000000200<BR>
+  #  EfiACPIMemoryNVS                  0x0000000000000400<BR>
+  #  EfiMemoryMappedIO                 0x0000000000000800<BR>
+  #  EfiMemoryMappedIOPortSpace        0x0000000000001000<BR>
+  #  EfiPalCode                        0x0000000000002000<BR>
+  #  EfiPersistentMemory               0x0000000000004000<BR>
+  #  OEM Reserved                      0x4000000000000000<BR>
+  #  OS Reserved                       0x8000000000000000<BR>
+  # e.g. LoaderCode+LoaderData+BootServicesCode+BootServicesData are needed, 0x1E should be used.<BR>
+  # @Prompt The memory type mask for Page Guard.
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType|0x0|UINT64|0x30001051
+
+  ## Indicates which type allocation need guard page.
+  # Below is bit mask for this PCD: (Order is same as UEFI spec)<BR>
+  #  EfiReservedMemoryType             0x0000000000000001<BR>
+  #  EfiLoaderCode                     0x0000000000000002<BR>
+  #  EfiLoaderData                     0x0000000000000004<BR>
+  #  EfiBootServicesCode               0x0000000000000008<BR>
+  #  EfiBootServicesData               0x0000000000000010<BR>
+  #  EfiRuntimeServicesCode            0x0000000000000020<BR>
+  #  EfiRuntimeServicesData            0x0000000000000040<BR>
+  #  EfiConventionalMemory             0x0000000000000080<BR>
+  #  EfiUnusableMemory                 0x0000000000000100<BR>
+  #  EfiACPIReclaimMemory              0x0000000000000200<BR>
+  #  EfiACPIMemoryNVS                  0x0000000000000400<BR>
+  #  EfiMemoryMappedIO                 0x0000000000000800<BR>
+  #  EfiMemoryMappedIOPortSpace        0x0000000000001000<BR>
+  #  EfiPalCode                        0x0000000000002000<BR>
+  #  EfiPersistentMemory               0x0000000000004000<BR>
+  #  OEM Reserved                      0x4000000000000000<BR>
+  #  OS Reserved                       0x8000000000000000<BR>
+  # e.g. LoaderCode+LoaderData+BootServicesCode+BootServicesData are needed, 0x1E should be used.<BR>
+  # @Prompt The memory type mask for Pool Guard.
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType|0x0|UINT64|0x30001052
+
+  ## This mask is to control Heap Guard behavior.
+  #   BIT0 - Enable UEFI page guard.<BR>
+  #   BIT1 - Enable UEFI pool guard.<BR>
+  #   BIT2 - Enable SMM page guard.<BR>
+  #   BIT3 - Enable SMM pool guard.<BR>
+  #   BIT7 - The direction of Guard Page for Pool Guard.
+  #          0 - The returned pool is adjacent to the bottom guard page.<BR>
+  #          1 - The returned pool is adjacent to the top guard page.<BR>
+  # @Prompt The Heap Guard feature mask
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask|0x0|UINT8|0x30001053
+
 [PcdsFixedAtBuild, PcdsPatchableInModule]
   ## Dynamic type PCD can be registered callback function for Pcd setting action.
   #  PcdMaxPeiPcdCallBackNumberPerPcdEntry indicates the maximum number of callback function
diff --git a/MdeModulePkg/MdeModulePkg.uni b/MdeModulePkg/MdeModulePkg.uni
index d6015de75f..74c27039bf 100644
--- a/MdeModulePkg/MdeModulePkg.uni
+++ b/MdeModulePkg/MdeModulePkg.uni
@@ -1127,3 +1127,61 @@
                                                                                                      "enabled on AMD processors supporting the Secure Encrypted Virtualization (SEV) feature.\n"
                                                                                                      "This mask should be applied when creating 1:1 virtual to physical mapping tables."
 
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPageType_PROMPT  #language en-US "The memory type mask for Page Guard"
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPageType_HELP    #language en-US "Indicates which type allocation need guard page.\n"
+                                                                                        " Below is bit mask for this PCD: (Order is same as UEFI spec)<BR>\n"
+                                                                                        "  EfiReservedMemoryType             0x0000000000000001\n"
+                                                                                        "  EfiLoaderCode                     0x0000000000000002\n"
+                                                                                        "  EfiLoaderData                     0x0000000000000004\n"
+                                                                                        "  EfiBootServicesCode               0x0000000000000008\n"
+                                                                                        "  EfiBootServicesData               0x0000000000000010\n"
+                                                                                        "  EfiRuntimeServicesCode            0x0000000000000020\n"
+                                                                                        "  EfiRuntimeServicesData            0x0000000000000040\n"
+                                                                                        "  EfiConventionalMemory             0x0000000000000080\n"
+                                                                                        "  EfiUnusableMemory                 0x0000000000000100\n"
+                                                                                        "  EfiACPIReclaimMemory              0x0000000000000200\n"
+                                                                                        "  EfiACPIMemoryNVS                  0x0000000000000400\n"
+                                                                                        "  EfiMemoryMappedIO                 0x0000000000000800\n"
+                                                                                        "  EfiMemoryMappedIOPortSpace        0x0000000000001000\n"
+                                                                                        "  EfiPalCode                        0x0000000000002000\n"
+                                                                                        "  EfiPersistentMemory               0x0000000000004000\n"
+                                                                                        "  OEM Reserved                      0x4000000000000000\n"
+                                                                                        "  OS Reserved                       0x8000000000000000\n"
+                                                                                        " e.g. LoaderCode+LoaderData+BootServicesCode+BootServicesData are needed, 0x1E should be used.<BR>"
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPoolType_PROMPT  #language en-US "The memory type mask for Pool Guard"
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPoolType_HELP    #language en-US "Indicates which type allocation need guard page.\n"
+                                                                                        " Below is bit mask for this PCD: (Order is same as UEFI spec)<BR>\n"
+                                                                                        "  EfiReservedMemoryType             0x0000000000000001\n"
+                                                                                        "  EfiLoaderCode                     0x0000000000000002\n"
+                                                                                        "  EfiLoaderData                     0x0000000000000004\n"
+                                                                                        "  EfiBootServicesCode               0x0000000000000008\n"
+                                                                                        "  EfiBootServicesData               0x0000000000000010\n"
+                                                                                        "  EfiRuntimeServicesCode            0x0000000000000020\n"
+                                                                                        "  EfiRuntimeServicesData            0x0000000000000040\n"
+                                                                                        "  EfiConventionalMemory             0x0000000000000080\n"
+                                                                                        "  EfiUnusableMemory                 0x0000000000000100\n"
+                                                                                        "  EfiACPIReclaimMemory              0x0000000000000200\n"
+                                                                                        "  EfiACPIMemoryNVS                  0x0000000000000400\n"
+                                                                                        "  EfiMemoryMappedIO                 0x0000000000000800\n"
+                                                                                        "  EfiMemoryMappedIOPortSpace        0x0000000000001000\n"
+                                                                                        "  EfiPalCode                        0x0000000000002000\n"
+                                                                                        "  EfiPersistentMemory               0x0000000000004000\n"
+                                                                                        "  OEM Reserved                      0x4000000000000000\n"
+                                                                                        "  OS Reserved                       0x8000000000000000\n"
+                                                                                        " e.g. LoaderCode+LoaderData+BootServicesCode+BootServicesData are needed, 0x1E should be used.<BR>"
+
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPropertyMask_PROMPT  #language en-US "The Heap Guard feature mask"
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdHeapGuardPropertyMask_HELP    #language en-US "This mask is to control Heap Guard behavior.\n"
+                                                                                            "   BIT0 - Enable UEFI page guard.<BR>\n"
+                                                                                            "   BIT1 - Enable UEFI pool guard.<BR>\n"
+                                                                                            "   BIT2 - Enable SMM page guard.<BR>\n"
+                                                                                            "   BIT3 - Enable SMM pool guard.<BR>\n"
+                                                                                            "   BIT7 - The direction of Guard Page for Pool Guard.\n"
+                                                                                            "          0 - The returned pool is adjacent to the bottom guard page.<BR>\n"
+                                                                                            "          1 - The returned pool is adjacent to the top guard page.<BR>"
+
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v2 4/6] UefiCpuPkg/CpuDxe: Reduce debug message
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
                   ` (2 preceding siblings ...)
  2017-10-17 13:29 ` [PATCH v2 3/6] MdeModulePkg/MdeModulePkg.dec, .uni: Add heap guard related PCDs and string tokens Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 5/6] UefiCpuPkg/PiSmmCpuDxeSmm: Disable page table protection Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 6/6] MdeModulePkg/DxeIpl: Enable paging for heap guard Jian J Wang
  5 siblings, 0 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Eric Dong

Heap guard feature will frequently update page attributes. The debug message
in CpuDxe driver will slow down the boot performance noticeably. Changing the
debug level to DEBUG_POOL and DEBUG_PAGE to reduce the message output for
normal debug configuration.

Cc: Eric Dong <eric.dong@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 UefiCpuPkg/CpuDxe/CpuPageTable.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c
index d312eb66f8..5270a1124f 100644
--- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
+++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
@@ -442,8 +442,9 @@ ConvertPageEntryAttribute (
   *PageEntry = NewPageEntry;
   if (CurrentPageEntry != NewPageEntry) {
     *IsModified = TRUE;
-    DEBUG ((DEBUG_INFO, "ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
-    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+    DEBUG ((DEBUG_POOL | DEBUG_PAGE, "ConvertPageEntryAttribute 0x%lx",
+            CurrentPageEntry));
+    DEBUG ((DEBUG_POOL | DEBUG_PAGE, "->0x%lx\n", NewPageEntry));
   } else {
     *IsModified = FALSE;
   }
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v2 5/6] UefiCpuPkg/PiSmmCpuDxeSmm: Disable page table protection
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
                   ` (3 preceding siblings ...)
  2017-10-17 13:29 ` [PATCH v2 4/6] UefiCpuPkg/CpuDxe: Reduce debug message Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  2017-10-17 13:29 ` [PATCH v2 6/6] MdeModulePkg/DxeIpl: Enable paging for heap guard Jian J Wang
  5 siblings, 0 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Eric Dong, Jiewen Yao

> According to Eric's feedback:
> a. Enclose bit-or with parentheses
> b. Add code in 32-bit code to bypass setting page table to read-only

Heap guard feature will update page attributes frequently. The page table
should not set to be read-only if heap guard feature is enabled for SMM
mode. Otherwise this feature cannot work.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c     | 7 +++++++
 UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf | 1 +
 UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c      | 3 ++-
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c
index f295c2ebf2..27c11f1b8d 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c
@@ -184,6 +184,13 @@ SetPageTableAttributes (
   BOOLEAN               IsSplitted;
   BOOLEAN               PageTableSplitted;
 
+  //
+  // Don't mark page table as read-only if heap guard is enabled.
+  //
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & (BIT3 | BIT2)) != 0) {
+    return ;
+  }
+
   DEBUG ((DEBUG_INFO, "SetPageTableAttributes\n"));
 
   //
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf
index 099792e6ce..644709650c 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf
@@ -159,6 +159,7 @@
   gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmStaticPageTable               ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdAcpiS3Enable                   ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
 
 [Depex]
   gEfiMpServiceProtocolGuid
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c
index 3dde80f9ba..4d4668a0c6 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c
@@ -902,7 +902,8 @@ SetPageTableAttributes (
   BOOLEAN               IsSplitted;
   BOOLEAN               PageTableSplitted;
 
-  if (!mCpuSmmStaticPageTable) {
+  if (!mCpuSmmStaticPageTable
+      || (PcdGet8 (PcdHeapGuardPropertyMask) & (BIT3 | BIT2)) != 0) {
     return ;
   }
 
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v2 6/6] MdeModulePkg/DxeIpl: Enable paging for heap guard
  2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
                   ` (4 preceding siblings ...)
  2017-10-17 13:29 ` [PATCH v2 5/6] UefiCpuPkg/PiSmmCpuDxeSmm: Disable page table protection Jian J Wang
@ 2017-10-17 13:29 ` Jian J Wang
  5 siblings, 0 replies; 13+ messages in thread
From: Jian J Wang @ 2017-10-17 13:29 UTC (permalink / raw)
  To: edk2-devel; +Cc: Star Zeng, Eric Dong, Jiewen Yao

Heap guard feature needs paging to work properly. 64-bit BIOS uses
PcdDxeIplBuildPageTables to control the page table setup. 32-bit BIOS
has to check heap guard feature to decide enabling paging or not.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
 MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf         |  1 +
 MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c | 29 ++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
index c54afe4aa6..1c48f80a76 100644
--- a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
@@ -115,6 +115,7 @@
 [Pcd.IA32,Pcd.X64]
   gEfiMdeModulePkgTokenSpaceGuid.PcdUse1GPageTable                      ## SOMETIMES_CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
 
 [Pcd.IA32,Pcd.X64,Pcd.ARM,Pcd.AARCH64]
   gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack               ## SOMETIMES_CONSUMES
diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index 1957326caf..306d7ec804 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -209,6 +209,33 @@ IsExecuteDisableBitAvailable (
   return Available;
 }
 
+/**
+  The function will check if page table should be setup or not.
+
+  @retval TRUE      Page table should be created.
+  @retval FALSE     Page table should not be created.
+
+**/
+BOOLEAN
+ToBuildPageTable (
+  VOID
+  )
+{
+  if (!IsIa32PaeSupport ()) {
+    return FALSE;
+  }
+
+  if (PcdGet8 (PcdHeapGuardPropertyMask) != 0) {
+    return TRUE;
+  }
+
+  if (PcdGetBool (PcdSetNxForStack) && IsExecuteDisableBitAvailable ()) {
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
 /**
    Transfers control to DxeCore.
 
@@ -379,7 +406,7 @@ HandOffToDxeCore (
     TopOfStack = (EFI_PHYSICAL_ADDRESS) (UINTN) ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
 
     PageTables = 0;
-    BuildPageTablesIa32Pae = (BOOLEAN) (PcdGetBool (PcdSetNxForStack) && IsIa32PaeSupport () && IsExecuteDisableBitAvailable ());
+    BuildPageTablesIa32Pae = ToBuildPageTable ();
     if (BuildPageTablesIa32Pae) {
       PageTables = Create4GPageTablesIa32Pae (BaseOfStack, STACK_SIZE);
       EnableExecuteDisableBit ();
-- 
2.14.1.windows.1



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-17 13:29 ` [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode Jian J Wang
@ 2017-10-18  5:07   ` Yao, Jiewen
  2017-10-18  5:51     ` Wang, Jian J
  0 siblings, 1 reply; 13+ messages in thread
From: Yao, Jiewen @ 2017-10-18  5:07 UTC (permalink / raw)
  To: Wang, Jian J, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-18  5:07   ` Yao, Jiewen
@ 2017-10-18  5:51     ` Wang, Jian J
  2017-10-18  5:54       ` Yao, Jiewen
  0 siblings, 1 reply; 13+ messages in thread
From: Wang, Jian J @ 2017-10-18  5:51 UTC (permalink / raw)
  To: Yao, Jiewen, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

Yes, we can. But that also means public interfaces changes, which might affect internal/external users. Any formal procedure required to make such kind of changes?

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:07 PM
To: Wang, Jian J <jian.j.wang@intel.com>; edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-18  5:51     ` Wang, Jian J
@ 2017-10-18  5:54       ` Yao, Jiewen
  2017-10-20  0:54         ` Wang, Jian J
  0 siblings, 1 reply; 13+ messages in thread
From: Yao, Jiewen @ 2017-10-18  5:54 UTC (permalink / raw)
  To: Wang, Jian J, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

I do not think there is interface *change*.
We can define a *new* interface in MdeModulePkg\Include\Protocol.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Wednesday, October 18, 2017 1:52 PM
To: Yao, Jiewen <jiewen.yao@intel.com>; edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Yes, we can. But that also means public interfaces changes, which might affect internal/external users. Any formal procedure required to make such kind of changes?

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:07 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-18  5:54       ` Yao, Jiewen
@ 2017-10-20  0:54         ` Wang, Jian J
  2017-10-20  1:36           ` Yao, Jiewen
  0 siblings, 1 reply; 13+ messages in thread
From: Wang, Jian J @ 2017-10-20  0:54 UTC (permalink / raw)
  To: Yao, Jiewen, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

I took a look at current available protocols and found that we have already gEfiSmmCpuProtocolGuid and gEfiSmmCpuServiceProtocolGuid. Just like gEfiCpuArchProtocolGuid which provides the API to update memory attributes (MTRR and paging), how about we add new interfaces to gEfiSmmCpuProtocolGuid or gEfiSmmCpuServiceProtocolGuid (I'm not sure which is more appropriate for this situation)?

gEfiSmmCpuProtocolGuid is defined in MdePkg. I would assume it's spec related. gEfiSmmCpuServiceProtocolGuid is defined in UefiCpuPkg, which looks like to be a better candidate.

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:55 PM
To: Wang, Jian J <jian.j.wang@intel.com>; edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I do not think there is interface *change*.
We can define a *new* interface in MdeModulePkg\Include\Protocol.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Wednesday, October 18, 2017 1:52 PM
To: Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Yes, we can. But that also means public interfaces changes, which might affect internal/external users. Any formal procedure required to make such kind of changes?

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:07 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-20  0:54         ` Wang, Jian J
@ 2017-10-20  1:36           ` Yao, Jiewen
  2017-10-20  1:49             ` Wang, Jian J
  0 siblings, 1 reply; 13+ messages in thread
From: Yao, Jiewen @ 2017-10-20  1:36 UTC (permalink / raw)
  To: Wang, Jian J, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

I remember MdeModulePkg cannot depend on UefiCpuPkg. Is that correct, Mike?

Maybe we can define a new one in MdeModulePkg, such as gEdkiiSmmMemoryAttributeProtocol.

Thank you
Yao Jiewen


From: Wang, Jian J
Sent: Friday, October 20, 2017 8:55 AM
To: Yao, Jiewen <jiewen.yao@intel.com>; edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I took a look at current available protocols and found that we have already gEfiSmmCpuProtocolGuid and gEfiSmmCpuServiceProtocolGuid. Just like gEfiCpuArchProtocolGuid which provides the API to update memory attributes (MTRR and paging), how about we add new interfaces to gEfiSmmCpuProtocolGuid or gEfiSmmCpuServiceProtocolGuid (I'm not sure which is more appropriate for this situation)?

gEfiSmmCpuProtocolGuid is defined in MdePkg. I would assume it's spec related. gEfiSmmCpuServiceProtocolGuid is defined in UefiCpuPkg, which looks like to be a better candidate.

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:55 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I do not think there is interface *change*.
We can define a *new* interface in MdeModulePkg\Include\Protocol.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Wednesday, October 18, 2017 1:52 PM
To: Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Yes, we can. But that also means public interfaces changes, which might affect internal/external users. Any formal procedure required to make such kind of changes?

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:07 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode
  2017-10-20  1:36           ` Yao, Jiewen
@ 2017-10-20  1:49             ` Wang, Jian J
  0 siblings, 0 replies; 13+ messages in thread
From: Wang, Jian J @ 2017-10-20  1:49 UTC (permalink / raw)
  To: Yao, Jiewen, edk2-devel@lists.01.org
  Cc: Zeng, Star, Dong, Eric, Kinney, Michael D

I forgot the dependency part. If so, it's ok to me to add a new protocol like gEdkiiSmmMemoryAttributeProtocol. I think this protocol will l be implemented in PiSmmCpuDxeSmm driver. If no other comments on this, I'll update the code and send the v3 patch soon.

From: Yao, Jiewen
Sent: Friday, October 20, 2017 9:37 AM
To: Wang, Jian J <jian.j.wang@intel.com>; edk2-devel@lists.01.org
Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I remember MdeModulePkg cannot depend on UefiCpuPkg. Is that correct, Mike?

Maybe we can define a new one in MdeModulePkg, such as gEdkiiSmmMemoryAttributeProtocol.

Thank you
Yao Jiewen


From: Wang, Jian J
Sent: Friday, October 20, 2017 8:55 AM
To: Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I took a look at current available protocols and found that we have already gEfiSmmCpuProtocolGuid and gEfiSmmCpuServiceProtocolGuid. Just like gEfiCpuArchProtocolGuid which provides the API to update memory attributes (MTRR and paging), how about we add new interfaces to gEfiSmmCpuProtocolGuid or gEfiSmmCpuServiceProtocolGuid (I'm not sure which is more appropriate for this situation)?

gEfiSmmCpuProtocolGuid is defined in MdePkg. I would assume it's spec related. gEfiSmmCpuServiceProtocolGuid is defined in UefiCpuPkg, which looks like to be a better candidate.

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:55 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

I do not think there is interface *change*.
We can define a *new* interface in MdeModulePkg\Include\Protocol.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Wednesday, October 18, 2017 1:52 PM
To: Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Yes, we can. But that also means public interfaces changes, which might affect internal/external users. Any formal procedure required to make such kind of changes?

From: Yao, Jiewen
Sent: Wednesday, October 18, 2017 1:07 PM
To: Wang, Jian J <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>; edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: RE: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

Hi
I am a little worried about adding page table management in PiSmmCore directly.

Can we define an interface between PiSmmCore and PiSmmCpu driver to set memory attribute? Like what we did in DxeCore and DxeCpu driver.

Thank you
Yao Jiewen

From: Wang, Jian J
Sent: Tuesday, October 17, 2017 9:29 PM
To: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org>
Cc: Zeng, Star <star.zeng@intel.com<mailto:star.zeng@intel.com>>; Dong, Eric <eric.dong@intel.com<mailto:eric.dong@intel.com>>; Yao, Jiewen <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>; Kinney, Michael D <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Subject: [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode

> According to Eric's feedback:
> a. Remove local variable initializer with memory copy from globals
> b. Change map table dump code to use DEBUG_PAGE|DEBUG_POOL level
>    message
> c. Remove unnecessary debug code
> d. Change name of function InitializePageTableLib to
>    InitializePageTableGlobals
>
> Other changes:
> e. Fix issues in 32-bit boot mode
> f. Coding style cleanup

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT2 and BIT3 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for SMM page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiRuntimeServicesCode
and EfiRuntimeServicesData by setting the PCD with value 0x60.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Cc: Star Zeng <star.zeng@intel.com<mailto:star.zeng@intel.com>>
Cc: Eric Dong <eric.dong@intel.com<mailto:eric.dong@intel.com>>
Cc: Jiewen Yao <jiewen.yao@intel.com<mailto:jiewen.yao@intel.com>>
Cc: Michael Kinney <michael.d.kinney@intel.com<mailto:michael.d.kinney@intel.com>>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com<mailto:ayellet.wolman@intel.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com<mailto:jian.j.wang@intel.com>>
---
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c | 1446 ++++++++++++++++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h |  400 +++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c |  704 +++++++++++++
 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h |  174 ++++
 MdeModulePkg/Core/PiSmmCore/Page.c           |   51 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.c      |   12 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.h      |   80 +-
 MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf    |    8 +
 MdeModulePkg/Core/PiSmmCore/Pool.c           |   75 +-
 9 files changed, 2922 insertions(+), 28 deletions(-)
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
 create mode 100644 MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h

diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
new file mode 100644
index 0000000000..5c97422bb6
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.c
@@ -0,0 +1,1446 @@
+/** @file
+  UEFI Heap Guard functions.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "HeapGuard.h"
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which  '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+                                    = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// SMM status flag
+//
+BOOLEAN mIsSmmCpuMode = FALSE;
+
+/**
+  Set corresponding bits in bitmap table to 1 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+SetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+              (UINT64)-1);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Set corresponding bits in bitmap table to 0 according to the address
+
+  @param[in]  Address     Start address to set for
+  @param[in]  BitNumber   Number of bits to set
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return VOID
+**/
+STATIC
+VOID
+ClearBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           Lsbs;
+  UINTN           Qwords;
+  UINTN           Msbs;
+  UINTN           StartBit;
+  UINTN           EndBit;
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs    = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+              GUARDED_HEAP_MAP_ENTRY_BITS;
+    Lsbs    = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+    Qwords  = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs    = BitNumber;
+    Lsbs    = 0;
+    Qwords  = 0;
+  }
+
+  if (Msbs > 0) {
+    *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+    BitMap  += 1;
+  }
+
+  if (Qwords > 0) {
+    SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+    BitMap += Qwords;
+  }
+
+  if (Lsbs > 0) {
+    *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+  }
+}
+
+/**
+  Get corresponding bits in bitmap table according to the address
+
+  The value of bit 0 corresponds to the status of memory at given Address.
+  No more than 64 bits can be retrieved in one call.
+
+  @param[in]  Address     Start address to retrieve bits for
+  @param[in]  BitNumber   Number of bits to get
+  @param[in]  BitMap      Pointer to bitmap which covers the Address
+
+  @return An integer containing the bits information
+**/
+STATIC
+UINT64
+GetBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   BitNumber,
+  IN UINT64                  *BitMap
+  )
+{
+  UINTN           StartBit;
+  UINTN           EndBit;
+  UINTN           Lsbs;
+  UINTN           Msbs;
+  UINT64          Result;
+
+  ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  StartBit  = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+  EndBit    = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+  if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+    Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+    Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+  } else {
+    Msbs = BitNumber;
+    Lsbs = 0;
+  }
+
+  Result    = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+  if (Lsbs > 0) {
+    BitMap  += 1;
+    Result  |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+  }
+
+  return Result;
+}
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    Memory;
+
+  Status = SmmInternalAllocatePages (AllocateAnyPages, EfiRuntimeServicesData,
+                                     Pages, &Memory, FALSE);
+  if (EFI_ERROR (Status)) {
+    Memory = 0;
+  }
+
+  return (VOID *)(UINTN)Memory;
+}
+
+/**
+  Locate the pointer of bitmap from the guarded memory bitmap tables, which
+  covers the given Address.
+
+  @param[in]  Address       Start address to search the bitmap for
+  @param[in]  AllocMapUnit  Flag to indicate memory allocation for the table
+  @param[out] BitMap        Pointer to bitmap which covers the Address
+
+  @return The bit number from given Address to the end of current map table
+**/
+UINTN
+FindGuardedMemoryMap (
+  IN  EFI_PHYSICAL_ADDRESS    Address,
+  IN  BOOLEAN                 AllocMapUnit,
+  OUT UINT64                  **BitMap
+  )
+{
+  UINTN                   Level;
+  UINT64                  *GuardMap;
+  UINT64                  MapMemory;
+  UINTN                   Index;
+  UINTN                   Size;
+  UINTN                   BitsToUnitEnd;
+
+  //
+  // Adjust current map table depth according to the address to access
+  //
+  while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
+         &&
+         RShiftU64 (
+           Address,
+           mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+           ) != 0) {
+
+    if (mGuardedMemoryMap != 0) {
+      Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+             * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+      *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+      mGuardedMemoryMap = MapMemory;
+    }
+
+    mMapLevel++;
+
+  }
+
+  GuardMap = &mGuardedMemoryMap;
+  for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+       Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+       ++Level) {
+
+    if (*GuardMap == 0) {
+      if (!AllocMapUnit) {
+        GuardMap = NULL;
+        break;
+      }
+
+      Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+      MapMemory = (UINT64)PageAlloc (EFI_SIZE_TO_PAGES (Size));
+      ASSERT (MapMemory != 0);
+
+      SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+      *GuardMap = MapMemory;
+    }
+
+    Index     = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+    Index     &= mLevelMask[Level];
+    GuardMap  = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+
+  }
+
+  BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+  *BitMap       = GuardMap;
+
+  return BitsToUnitEnd;
+}
+
+/**
+  Set corresponding bits in bitmap table to 1 according to given memory range
+
+  @param[in]  Address       Memory address to guard from
+  @param[in]  NumberOfPages Number of pages to guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    SetBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Clear corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to unset from
+  @param[in]  NumberOfPages Number of pages to unset guard
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             BitsToUnitEnd;
+
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+    ASSERT (BitMap != NULL);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    ClearBits (Address, Bits, BitMap);
+
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+}
+
+/**
+  Retrieve corresponding bits in bitmap table according to given memory range
+
+  @param[in]  Address       Memory address to retrieve from
+  @param[in]  NumberOfPages Number of pages to retrieve
+
+  @return VOID
+**/
+UINTN
+GetGuardedMemoryBits (
+  IN EFI_PHYSICAL_ADDRESS    Address,
+  IN UINTN                   NumberOfPages
+  )
+{
+  UINT64            *BitMap;
+  UINTN             Bits;
+  UINTN             Result;
+  UINTN             Shift;
+  UINTN             BitsToUnitEnd;
+
+  ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+  Result = 0;
+  Shift  = 0;
+  while (NumberOfPages > 0) {
+    BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+    if (NumberOfPages > BitsToUnitEnd) {
+      // Cross map unit
+      Bits  = BitsToUnitEnd;
+    } else {
+      Bits  = NumberOfPages;
+    }
+
+    if (BitMap != NULL) {
+      Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+    }
+
+    Shift         += Bits;
+    NumberOfPages -= Bits;
+    Address       += EFI_PAGES_TO_SIZE (Bits);
+  }
+
+  return Result;
+}
+
+/**
+  Get bit value in bitmap table for the given address
+
+  @param[in]  Address     The address to retrieve for
+
+  @return 1 or 0
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+
+  FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+  if (GuardMap != NULL) {
+    if (RShiftU64 (*GuardMap,
+                   GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/**
+  Set the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to set for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap |= BitMask;
+  }
+}
+
+/**
+  Clear the bit in bitmap table for the given address
+
+  @param[in]  Address     The address to clear for
+
+  @return VOID
+**/
+VOID
+EFIAPI
+ClearGuardMapBit (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINT64        *GuardMap;
+  UINT64        BitMask;
+
+  FindGuardedMemoryMap (Address, TRUE, &GuardMap);
+  if (GuardMap != NULL) {
+    BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
+    *GuardMap &= ~BitMask;
+  }
+}
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  UINTN       BitMap;
+
+  BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+  return (BitMap == 0b001 || BitMap == 0b100 || BitMap == 0b101);
+}
+
+/**
+  Check to see if the page at the given address is a head Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a head Guard page
+  @return FALSE The page at Address is not a head Guard page
+**/
+BOOLEAN
+EFIAPI
+IsHeadGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address, 2) == 0b10);
+}
+
+/**
+  Check to see if the page at the given address is a tail Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a tail Guard page
+  @return FALSE The page at Address is not a tail Guard page
+**/
+BOOLEAN
+EFIAPI
+IsTailGuard (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
+}
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  )
+{
+  return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+  Set the page at the given address to be a Guard page.
+
+  This is done by changing the page table attribute to be NOT PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmSetMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Unset the Guard page at the given address to the normal memory.
+
+  This is done by changing the page table attribute to be PRSENT.
+
+  @param[in]  Address     Page address to Guard at
+
+  @return VOID
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress
+  )
+{
+  if (mIsSmmCpuMode) {
+    SmmClearMemoryAttributes (BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+  }
+}
+
+/**
+  Check to see if the memory at the given address should be guarded or not
+
+  @param[in]  MemoryType      Memory type to check
+  @param[in]  AllocateType    Allocation type to check
+  @param[in]  PageOrPool      Indicate a page allocation or pool allocation
+
+
+  @return TRUE  The given type of memory should be guarded
+  @return FALSE The given type of memory should not be guarded
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType,
+  IN UINT8                  PageOrPool
+  )
+{
+  UINT64 TestBit;
+  UINT64 ConfigBit;
+
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0 ||
+      AllocateType == AllocateAddress) {
+    return FALSE;
+  }
+
+  ConfigBit = 0;
+  if (PageOrPool & GUARD_HEAP_TYPE_POOL) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPoolType);
+  }
+
+  if (PageOrPool & GUARD_HEAP_TYPE_PAGE) {
+    ConfigBit |= PcdGet64 (PcdHeapGuardPageType);
+  }
+
+  if (MemoryType == EfiRuntimeServicesData ||
+      MemoryType == EfiRuntimeServicesCode) {
+    TestBit = LShiftU64 (1, MemoryType);
+  } else if (MemoryType == EfiMaxMemoryType) {
+    TestBit = (UINT64)-1;
+  } else {
+    TestBit = 0;
+  }
+
+  return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL);
+}
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  )
+{
+  return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  )
+{
+  return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,
+                              GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS    GuardPage;
+
+  //
+  // Set tail Guard
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  // Set head Guard
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (!IsGuardPage (GuardPage)) {
+    SetGuardPage (GuardPage);
+  }
+
+  //
+  // Mark the memory range as Guarded
+  //
+  SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  GuardPage;
+
+  if (NumberOfPages == 0) {
+    return;
+  }
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // unset it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. Turn first page of memory block to free into a new Guard.
+    //
+    SetGuardPage (Memory);
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+  if (IsTailGuard (GuardPage)) {
+    if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      UnsetGuardPage (GuardPage);
+    }
+  } else if (IsMemoryGuarded (GuardPage)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+  }
+
+  //
+  // No matter what, we just clear the mark of the Guarded memory.
+  //
+  ClearGuardedMemoryBits(Memory, NumberOfPages);
+}
+
+/**
+  Adjust address of free memory according to existing and/or required Guard
+
+  This function will check if there're existing Guard pages of adjacent
+  memory blocks, and try to use it as the Guard page of the memory to be
+  allocated.
+
+  @param[in]  Start           Start address of free memory block
+  @param[in]  Size            Size of free memory block
+  @param[in]  SizeRequested   Size of memory to allocate
+
+  @return The end address of memory block found
+  @return 0 if no enough space for the required size of memory and its Guard
+**/
+UINT64
+AdjustMemoryS (
+  IN UINT64                  Start,
+  IN UINT64                  Size,
+  IN UINT64                  SizeRequested
+  )
+{
+  UINT64  Target;
+
+  Target = Start + Size - SizeRequested;
+
+  //
+  // At least one more page needed for Guard page.
+  //
+  if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
+    return 0;
+  }
+
+  if (!IsGuardPage (Start + Size)) {
+    // No Guard at tail to share. One more page is needed.
+    Target -= EFI_PAGES_TO_SIZE (1);
+  }
+
+  // Out of range?
+  if (Target < Start) {
+    return 0;
+  }
+
+  // At the edge?
+  if (Target == Start) {
+    if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+      // No enough space for a new head Guard if no Guard at head to share.
+      return 0;
+    }
+  }
+
+  // OK, we have enough pages for memory and its Guards. Return the End of the
+  // free space.
+  return Target + SizeRequested - 1;
+}
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  EFI_PHYSICAL_ADDRESS  Start;
+  EFI_PHYSICAL_ADDRESS  MemoryToTest;
+  UINTN                 PagesToFree;
+
+  if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
+    return;
+  }
+
+  Start = *Memory;
+  PagesToFree = *NumberOfPages;
+
+  //
+  // Head Guard must be one page before, if any.
+  //
+  MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
+  if (IsHeadGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the head Guard is not a tail Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      Start       -= EFI_PAGES_TO_SIZE (1);
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages before memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a tail Guard.
+    //
+    Start       += EFI_PAGES_TO_SIZE (1);
+    PagesToFree -= 1;
+  }
+
+  //
+  // Tail Guard must be the page after this memory block to free, if any.
+  //
+  MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+  if (IsTailGuard (MemoryToTest)) {
+    if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
+      //
+      // If the tail Guard is not a head Guard of adjacent memory block,
+      // free it; otherwise, keep it.
+      //
+      PagesToFree += 1;
+    }
+  } else if (IsMemoryGuarded (MemoryToTest)) {
+    //
+    // Pages after memory to free are still in Guard. It's a partial free
+    // case. We need to keep one page to be a head Guard.
+    //
+    PagesToFree -= 1;
+  }
+
+  *Memory         = Start;
+  *NumberOfPages  = PagesToFree;
+}
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  )
+{
+  //
+  // FindFreePages() has already taken the Guard into account. It's safe to
+  // adjust the start address and/or number of pages here, to make sure that
+  // the Guards are also "allocated".
+  //
+  if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+    // No tail Guard, add one.
+    *NumberOfPages += 1;
+  }
+
+  if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+    // No head Guard, add one.
+    *Memory        -= EFI_PAGE_SIZE;
+    *NumberOfPages += 1;
+  }
+}
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  )
+{
+  if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
+    //
+    // Pool head is put near the head Guard
+    //
+    return (VOID *)(UINTN)Memory;
+  }
+
+  //
+  // Pool head is put near the tail Guard
+  //
+  return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+
+  )
+{
+  LIST_ENTRY      *Node;
+  FREE_PAGE_LIST  *Pages;
+  UINTN           PagesToAlloc;
+  UINTN           HeadGuard;
+  UINTN           TailGuard;
+  UINTN           Address;
+
+  for (Node = FreePageList->BackLink; Node != FreePageList;
+        Node = Node->BackLink) {
+    Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
+    if (Pages->NumberOfPages >= NumberOfPages &&
+        (UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
+
+      //
+      // We may need 1 or 2 more pages for Guard. Check it out.
+      //
+      PagesToAlloc = NumberOfPages;
+      TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
+      if (!IsGuardPage (TailGuard)) {
+        //
+        // Add one if no Guard at the end of current free memory block.
+        //
+        PagesToAlloc += 1;
+        TailGuard     = 0;
+      }
+
+      HeadGuard = (UINTN)Pages +
+                  EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
+                  EFI_PAGE_SIZE;
+      if (!IsGuardPage (HeadGuard)) {
+        //
+        // Add one if no Guard at the page before the address to allocate
+        //
+        PagesToAlloc += 1;
+        HeadGuard     = 0;
+      }
+
+      if (Pages->NumberOfPages < PagesToAlloc) {
+        // Not enough space to allocate memory with Guards? Try next block.
+        continue;
+      }
+
+      Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
+      ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
+      CoreFreeMemoryMapStack();
+      if (!HeadGuard) {
+        // Don't pass the Guard page to user.
+        Address += EFI_PAGE_SIZE;
+      }
+      SetGuardForMemory (Address, NumberOfPages);
+      return Address;
+    }
+  }
+
+  return (UINTN)(-1);
+}
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  )
+{
+  EFI_PHYSICAL_ADDRESS    MemoryToFree;
+  UINTN                   PagesToFree;
+
+  MemoryToFree  = Memory;
+  PagesToFree   = NumberOfPages;
+
+  AdjustMemoryF (&MemoryToFree, &PagesToFree);
+  UnsetGuardForMemory (Memory, NumberOfPages);
+
+  return SmmInternalFreePagesEx (MemoryToFree, PagesToFree, AddRegion);
+}
+
+/**
+  Set all Guard pages which cannot be set during the non-SMM mode time
+**/
+VOID
+SetAllGuardPages (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  UINT64    GuardPage;
+  INTN      Level;
+  UINTN     Index;
+  BOOLEAN   OnGuarding;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+  SetMem (Indices, sizeof(Indices), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  OnGuarding    = FALSE;
+
+  DEBUG_CODE (
+    DumpGuardedMemoryBitmap ();
+  );
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+      Tables[Level] = 0;
+      Level        -= 1;
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        OnGuarding = FALSE;
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+
+        continue;
+
+      } else {
+
+        Index = 0;
+        while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+          if ((TableEntry & 1) == 1) {
+            if (OnGuarding) {
+              GuardPage = 0;
+            } else {
+              GuardPage = Address - EFI_PAGE_SIZE;
+            }
+            OnGuarding = TRUE;
+          } else {
+            if (OnGuarding) {
+              GuardPage = Address;
+            } else {
+              GuardPage = 0;
+            }
+            OnGuarding = FALSE;
+          }
+
+          if (GuardPage != 0) {
+            SetGuardPage (GuardPage);
+          }
+
+          if (TableEntry == 0) {
+            break;
+          }
+
+          TableEntry = RShiftU64 (TableEntry, 1);
+          Address   += EFI_PAGE_SIZE;
+          Index     += 1;
+        }
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *SmmCpu;
+
+  if (!mIsSmmCpuMode) {
+    Status = SmmLocateProtocol (&gEfiSmmCpuProtocolGuid, NULL, &SmmCpu);
+    if (!EFI_ERROR(Status)) {
+      mIsSmmCpuMode = TRUE;
+      SetAllGuardPages ();
+    }
+  }
+}
+
+/**
+  Helper function to convert a UINT64 value in binary to a string
+
+  @param[in]  Value       Value of a UINT64 integer
+  @param[in]  BinString   String buffer to contain the conversion result
+
+  @return VOID
+**/
+VOID
+Uint64ToBinString (
+  IN  UINT64      Value,
+  OUT CHAR8       *BinString
+  )
+{
+  UINTN Index;
+
+  if (BinString == NULL) {
+    return;
+  }
+
+  for (Index = 64; Index > 0; --Index) {
+    BinString[Index - 1] = '0' + (Value & 1);
+    Value = RShiftU64 (Value, 1);
+  }
+  BinString[64] = '\0';
+}
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  )
+{
+  UINTN     Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINTN     Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+  UINT64    TableEntry;
+  UINT64    Address;
+  INTN      Level;
+  UINTN     RepeatZero;
+  CHAR8     String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+  CHAR8     *Ruler1;
+  CHAR8     *Ruler2;
+
+  if (mGuardedMemoryMap == 0) {
+    return;
+  }
+
+  Ruler1 = "               3               2               1               0";
+  Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
+                                  " Guarded Memory Bitmap "
+                                  "==============================\r\n"));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler1));
+  DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "                  %a\r\n", Ruler2));
+
+  CopyMem (Entries, mLevelMask, sizeof (Entries));
+  CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+  SetMem (Indices, sizeof(Indices), 0);
+  SetMem (Tables, sizeof(Tables), 0);
+  SetMem (Addresses, sizeof(Addresses), 0);
+
+  Level         = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+  Tables[Level] = mGuardedMemoryMap;
+  Address       = 0;
+  RepeatZero    = 0;
+
+  while (TRUE) {
+    if (Indices[Level] > Entries[Level]) {
+
+      Tables[Level] = 0;
+      Level        -= 1;
+      RepeatZero    = 0;
+
+      DEBUG ((
+        HEAP_GUARD_DEBUG_LEVEL,
+        "========================================="
+        "=========================================\r\n"
+        ));
+
+    } else {
+
+      TableEntry  = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+      Address     = Addresses[Level];
+
+      if (TableEntry == 0) {
+
+        if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+          if (RepeatZero == 0) {
+            Uint64ToBinString(TableEntry, String);
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+          } else if (RepeatZero == 1) {
+            DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "...             : ...\r\n"));
+          }
+          RepeatZero += 1;
+        }
+
+      } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+
+        Level            += 1;
+        Tables[Level]     = TableEntry;
+        Addresses[Level]  = Address;
+        Indices[Level]    = 0;
+        RepeatZero        = 0;
+
+        continue;
+
+      } else {
+
+        RepeatZero = 0;
+        Uint64ToBinString(TableEntry, String);
+        DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+
+      }
+    }
+
+    if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+      break;
+    }
+
+    Indices[Level] += 1;
+    Address = (Level == 0) ? 0 : Addresses[Level - 1];
+    Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
+
+  }
+}
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  )
+{
+  UINT64                *PageEntry;
+  PAGE_ATTRIBUTE        Attribute;
+  EFI_PHYSICAL_ADDRESS  Address;
+
+  if (!mIsSmmCpuMode) {
+    return TRUE;
+  }
+
+  Address = BaseAddress - EFI_PAGE_SIZE;
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  Address = BaseAddress + EFI_PAGES_TO_SIZE (NumberOfPages);
+  PageEntry = GetPageTableEntry (Address, &Attribute);
+  if (PageEntry == NULL || Attribute != Page4K) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx!!!\r\n", Address));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  if ((*PageEntry & IA32_PG_P) != 0) {
+    DEBUG ((DEBUG_ERROR, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
+            Address, *PageEntry));
+    DumpGuardedMemoryBitmap ();
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
new file mode 100644
index 0000000000..0a20226173
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/HeapGuard.h
@@ -0,0 +1,400 @@
+/** @file
+  Data structure and functions to allocate and free memory space.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _HEAPGUARD_H_
+#define _HEAPGUARD_H_
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+//
+// Following macros are used to define and access the guarded memory bitmap
+// table.
+//
+// To simplify the access and reduce the memory used for this table, the
+// table is constructed in the similar way as page table structure but in
+// reverse direction, i.e. from bottom growing up to top.
+//
+//    - 1-bit tracks 1 page (4KB)
+//    - 1-UINT64 map entry tracks 256KB memory
+//    - 1K-UINT64 map table tracks 256MB memory
+//    - Five levels of tables can track any address of memory of 64-bit
+//      system, like below.
+//
+//       512   *   512   *   512   *   512    *    1K   *  64b *     4K
+//    111111111 111111111 111111111 111111111 1111111111 111111 111111111111
+//    63        54        45        36        27         17     11         0
+//       9b        9b        9b        9b         10b      6b       12b
+//       L0   ->   L1   ->   L2   ->   L3   ->    L4   -> bits  ->  page
+//      1FF       1FF       1FF       1FF         3FF      3F       FFF
+//
+// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB
+// memory. Each table of L0-L3 will be allocated when its memory address
+// range is to be tracked. Only 1-page will be allocated each time. This
+// can save memories used to establish this map table.
+//
+// For a normal configuration of system with 4G memory, two levels of tables
+// can track the whole memory, because two levels (L3+L4) of map tables have
+// already coverred 37-bit of memory address. And for a normal UEFI BIOS,
+// less than 128M memory would be consumed during boot. That means we just
+// need
+//
+//          1-page (L3) + 2-page (L4)
+//
+// memory (3 pages) to track the memory allocation works. In this case,
+// there's no need to setup L0-L2 tables.
+//
+
+//
+// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9
+// bits in address. (512 = 1 << 9)
+//
+#define BYTE_LENGTH_SHIFT                   3             // (8 = 1 << 3)
+
+#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT  \
+        (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT)
+
+#define GUARDED_HEAP_MAP_TABLE_DEPTH        5
+
+// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may
+#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT    6             // (64 = 1 << 6)
+
+#define GUARDED_HEAP_MAP_ENTRY_BITS         \
+        (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)
+
+#define GUARDED_HEAP_MAP_ENTRY_BYTES        \
+        (GUARDED_HEAP_MAP_ENTRY_BITS / 8)
+
+// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b
+#define GUARDED_HEAP_MAP_ENTRY_SHIFT              \
+        (GUARDED_HEAP_MAP_ENTRY_BITS              \
+         - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \
+         - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT       \
+         - EFI_PAGE_SHIFT)
+
+// L4 table address mask: (1 << 10 - 1) = 0x3FF
+#define GUARDED_HEAP_MAP_ENTRY_MASK               \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1)
+
+// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page
+#define GUARDED_HEAP_MAP_SIZE                     \
+        ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB
+#define GUARDED_HEAP_MAP_UNIT_SIZE                \
+        (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE)
+
+// L4 table entry number: 8KB / 8 = 1024
+#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT         \
+        (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES)
+
+// L4 table entry indexing
+#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address)                       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT                         \
+                             + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)    \
+         & GUARDED_HEAP_MAP_ENTRY_MASK)
+
+// L4 table entry bit indexing
+#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address)       \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)            \
+         & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1))
+
+//
+// Total bits (pages) tracked by one L4 table (65536-bit)
+//
+#define GUARDED_HEAP_MAP_BITS                               \
+        (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+               + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT))
+
+//
+// Bit indexing inside the whole L4 table (0 - 65535)
+//
+#define GUARDED_HEAP_MAP_BIT_INDEX(Address)                     \
+        (RShiftU64 (Address, EFI_PAGE_SHIFT)                    \
+         & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT                 \
+                   + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1))
+
+//
+// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28
+//
+#define GUARDED_HEAP_MAP_TABLE_SHIFT                                      \
+        (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT  \
+         + EFI_PAGE_SHIFT)
+
+//
+// Macro used to initialize the local array variable for map table traversing
+// {55, 46, 37, 28, 18}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS                                 \
+  {                                                                         \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2,  \
+    GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT,      \
+    GUARDED_HEAP_MAP_TABLE_SHIFT,                                           \
+    EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT                       \
+  }
+
+//
+// Masks used to extract address range of each level of table
+// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF}
+//
+#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS                                  \
+  {                                                                         \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1,                          \
+    (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1                                 \
+  }
+
+//
+// Memory type to guard (matching the related PCD definition)
+//
+#define GUARD_HEAP_TYPE_POOL        BIT2
+#define GUARD_HEAP_TYPE_PAGE        BIT3
+
+//
+// Debug message level
+//
+#define HEAP_GUARD_DEBUG_LEVEL  (DEBUG_POOL|DEBUG_PAGE)
+
+typedef struct {
+  UINT32                TailMark;
+  UINT32                HeadMark;
+  EFI_PHYSICAL_ADDRESS  Address;
+  LIST_ENTRY            Link;
+} HEAP_GUARD_NODE;
+
+/**
+  Set head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to set guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+SetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Unset head Guard and tail Guard for the given memory range
+
+  @param[in]  Memory          Base address of memory to unset guard for
+  @param[in]  NumberOfPages   Memory size in pages
+
+  @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+  IN EFI_PHYSICAL_ADDRESS   Memory,
+  IN UINTN                  NumberOfPages
+  );
+
+/**
+  Adjust the base and number of pages to really allocate according to Guard
+
+  @param[in/out]  Memory          Base address of free memory
+  @param[in/out]  NumberOfPages   Size of memory to allocate
+
+  @return VOID
+**/
+VOID
+AdjustMemoryA (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Adjust the start address and number of pages to free according to Guard
+
+  The purpose of this function is to keep the shared Guard page with adjacent
+  memory block if it's still in guard, or free it if no more sharing. Another
+  is to reserve pages as Guard pages in partial page free situation.
+
+  @param[in/out]  Memory          Base address of memory to free
+  @param[in/out]  NumberOfPages   Size of memory to free
+
+  @return VOID
+**/
+VOID
+AdjustMemoryF (
+  IN OUT EFI_PHYSICAL_ADDRESS    *Memory,
+  IN OUT UINTN                   *NumberOfPages
+  );
+
+/**
+  Check to see if the pool at the given address should be guarded or not
+
+  @param[in]  MemoryType      Pool type to check
+
+
+  @return TRUE  The given type of pool should be guarded
+  @return FALSE The given type of pool should not be guarded
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType
+  );
+
+/**
+  Check to see if the page at the given address should be guarded or not
+
+  @param[in]  MemoryType      Page type to check
+  @param[in]  AllocateType    Allocation type to check
+
+  @return TRUE  The given type of page should be guarded
+  @return FALSE The given type of page should not be guarded
+**/
+BOOLEAN
+IsPageTypeToGuard (
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN EFI_ALLOCATE_TYPE      AllocateType
+  );
+
+/**
+  Check to see if the page at the given address is guarded or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is guarded
+  @return FALSE The page at Address is not guarded
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Check to see if the page at the given address is a Guard page or not
+
+  @param[in]  Address     The address to check for
+
+  @return TRUE  The page at Address is a Guard page
+  @return FALSE The page at Address is not a Guard page
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+  IN EFI_PHYSICAL_ADDRESS    Address
+  );
+
+/**
+  Dump the guarded memory bit map
+
+  @return VOID
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+  VOID
+  );
+
+/**
+  Adjust the pool head position to make sure the Guard page is adjavent to
+  pool tail or pool head.
+
+  @param[in]  Memory    Base address of memory allocated
+  @param[in]  NoPages   Number of pages actually allocated
+  @param[in]  Size      Size of memory requested
+                        (plus pool head/tail overhead)
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadA (
+  IN EFI_PHYSICAL_ADDRESS    Memory,
+  IN UINTN                   NoPages,
+  IN UINTN                   Size
+  );
+
+/**
+  Get the page base address according to pool head address
+
+  @param[in]  Memory    Head address of pool to free
+
+  @return Address of pool head
+**/
+VOID *
+AdjustPoolHeadF (
+  IN EFI_PHYSICAL_ADDRESS    Memory
+  );
+
+/**
+  Helper function of memory allocation with Guard pages
+
+  @param  FreePageList           The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+  @param  MemoryType             Type of memory requested.
+
+  @return Memory address of allocated pages.
+**/
+UINTN
+InternalAllocMaxAddressWithGuard (
+  IN OUT LIST_ENTRY           *FreePageList,
+  IN     UINTN                NumberOfPages,
+  IN     UINTN                MaxAddress,
+  IN     EFI_MEMORY_TYPE      MemoryType
+  );
+
+/**
+  Helper function of memory free with Guard pages
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+**/
+EFI_STATUS
+SmmInternalFreePagesExWithGuard (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Check to see if the heap guard is enabled for page and/or pool allocation
+
+  @return TRUE/FALSE
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+  VOID
+  );
+
+/**
+  Debug function used to verify if the Guard page is well set or not
+
+  @param[in]  BaseAddress     Address of memory to check
+  @param[in]  NumberOfPages   Size of memory in pages
+
+  @return TRUE    The head Guard and tail Guard are both well set
+  @return FALSE   The head Guard and/or tail Guard are not well set
+**/
+BOOLEAN
+VerifyMemoryGuard (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINTN                     NumberOfPages
+  );
+
+extern BOOLEAN mOnGuarding;
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
new file mode 100644
index 0000000000..0fbd3a7e0b
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.c
@@ -0,0 +1,704 @@
+/** @file
+
+Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "PiSmmCore.h"
+#include "PageTable.h"
+
+#include <Library/CpuLib.h>
+
+UINT64 mAddressEncMask = 0;
+UINT8  mPhysicalAddressBits = 32;
+
+PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
+  {PageNone,       0,                         0},
+  {Page4K,  SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
+  {Page2M,  SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
+  {Page1G,  SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
+};
+
+/**
+  Calculate the maximum support address.
+
+  @return the maximum support address.
+**/
+UINT8
+CalculateMaximumSupportAddress (
+  VOID
+  )
+{
+  UINT32                                        RegEax;
+  UINT8                                         PhysicalAddressBits;
+  VOID                                          *Hob;
+
+  //
+  // Get physical address bits supported.
+  //
+  Hob = GetFirstHob (EFI_HOB_TYPE_CPU);
+  if (Hob != NULL) {
+    PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;
+  } else {
+    AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
+    if (RegEax >= 0x80000008) {
+      AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
+      PhysicalAddressBits = (UINT8) RegEax;
+    } else {
+      PhysicalAddressBits = 36;
+    }
+  }
+
+  //
+  // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.
+  //
+  ASSERT (PhysicalAddressBits <= 52);
+  if (PhysicalAddressBits > 48) {
+    PhysicalAddressBits = 48;
+  }
+  return PhysicalAddressBits;
+}
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  )
+{
+  return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
+}
+
+/**
+  Return length according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The length of page entry.
+**/
+UINTN
+PageAttributeToLength (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].Length;
+  }
+  return 0;
+}
+
+/**
+  Return address mask according to page attributes.
+
+  @param[in]  PageAttributes   The page attribute of the page entry.
+
+  @return The address mask of page entry.
+**/
+UINTN
+PageAttributeToMask (
+  IN PAGE_ATTRIBUTE  PageAttribute
+  )
+{
+  if (PageAttribute <= Page1G) {
+    return (UINTN)mPageAttributeTable[PageAttribute].AddressMask;
+  }
+  return 0;
+}
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  )
+{
+  UINTN                 Index1;
+  UINTN                 Index2;
+  UINTN                 Index3;
+  UINTN                 Index4;
+  UINT64                *L1PageTable;
+  UINT64                *L2PageTable;
+  UINT64                *L3PageTable;
+  UINT64                *L4PageTable;
+
+  Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
+  Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
+  Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
+  Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
+
+  if (sizeof(UINTN) == sizeof(UINT64)) {
+    L4PageTable = (UINT64 *)GetPageTableBase ();
+    if (L4PageTable[Index4] == 0) {
+      *PageAttribute = PageNone;
+      return NULL;
+    }
+
+    L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  } else {
+    L3PageTable = (UINT64 *)GetPageTableBase ();
+  }
+  if (L3PageTable[Index3] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
+    // 1G
+    *PageAttribute = Page1G;
+    return &L3PageTable[Index3];
+  }
+
+  L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if (L2PageTable[Index2] == 0) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
+    // 2M
+    *PageAttribute = Page2M;
+    return &L2PageTable[Index2];
+  }
+
+  // 4k
+  L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~mAddressEncMask & PAGING_4K_ADDRESS_MASK_64);
+  if ((L1PageTable[Index1] == 0) && (Address != 0)) {
+    *PageAttribute = PageNone;
+    return NULL;
+  }
+  *PageAttribute = Page4K;
+  return &L1PageTable[Index1];
+}
+
+/**
+  Return memory attributes of page entry.
+
+  @param[in]  PageEntry        The page entry.
+
+  @return Memory attributes of page entry.
+**/
+UINT64
+GetAttributesFromPageEntry (
+  IN  UINT64                            *PageEntry
+  )
+{
+  UINT64  Attributes;
+  Attributes = 0;
+  if ((*PageEntry & IA32_PG_P) == 0) {
+    Attributes |= EFI_MEMORY_RP;
+  }
+  if ((*PageEntry & IA32_PG_RW) == 0) {
+    Attributes |= EFI_MEMORY_RO;
+  }
+  if ((*PageEntry & IA32_PG_NX) != 0) {
+    Attributes |= EFI_MEMORY_XP;
+  }
+  return Attributes;
+}
+
+/**
+  Modify memory attributes of page entry.
+
+  @param[in]   PageEntry        The page entry.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+**/
+VOID
+ConvertPageEntryAttribute (
+  IN  UINT64                            *PageEntry,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsModified
+  )
+{
+  UINT64  CurrentPageEntry;
+  UINT64  NewPageEntry;
+
+  CurrentPageEntry = *PageEntry;
+  NewPageEntry = CurrentPageEntry;
+  if ((Attributes & EFI_MEMORY_RP) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_P;
+    } else {
+      NewPageEntry |= IA32_PG_P;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_RO) != 0) {
+    if (IsSet) {
+      NewPageEntry &= ~(UINT64)IA32_PG_RW;
+    } else {
+      NewPageEntry |= IA32_PG_RW;
+    }
+  }
+  if ((Attributes & EFI_MEMORY_XP) != 0) {
+    if (IsSet) {
+      NewPageEntry |= IA32_PG_NX;
+    } else {
+      NewPageEntry &= ~IA32_PG_NX;
+    }
+  }
+
+  if (CurrentPageEntry != NewPageEntry) {
+    *PageEntry = NewPageEntry;
+    *IsModified = TRUE;
+    DEBUG ((DEBUG_INFO, "(SMM)ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
+    DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
+  } else {
+    *IsModified = FALSE;
+  }
+}
+
+/**
+  This function returns if there is need to split page entry.
+
+  @param[in]  BaseAddress      The base address to be checked.
+  @param[in]  Length           The length to be checked.
+  @param[in]  PageEntry        The page entry to be checked.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+
+  @retval SplitAttributes on if there is need to split page entry.
+**/
+PAGE_ATTRIBUTE
+NeedSplitPage (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute
+  )
+{
+  UINT64                PageEntryLength;
+
+  PageEntryLength = PageAttributeToLength (PageAttribute);
+
+  if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
+    return PageNone;
+  }
+
+  if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
+    return Page4K;
+  }
+
+  return Page2M;
+}
+
+/**
+  This function splits one page entry to small page entries.
+
+  @param[in]  PageEntry        The page entry to be splitted.
+  @param[in]  PageAttribute    The page attribute of the page entry.
+  @param[in]  SplitAttribute   How to split the page entry.
+
+  @retval RETURN_SUCCESS            The page entry is splitted.
+  @retval RETURN_UNSUPPORTED        The page entry does not support to be splitted.
+  @retval RETURN_OUT_OF_RESOURCES   No resource to split page entry.
+**/
+RETURN_STATUS
+SplitPage (
+  IN  UINT64                            *PageEntry,
+  IN  PAGE_ATTRIBUTE                    PageAttribute,
+  IN  PAGE_ATTRIBUTE                    SplitAttribute
+  )
+{
+  UINT64   BaseAddress;
+  UINT64   *NewPageEntry;
+  UINTN    Index;
+
+  ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
+
+  if (PageAttribute == Page2M) {
+    //
+    // Split 2M to 4K
+    //
+    ASSERT (SplitAttribute == Page4K);
+    if (SplitAttribute == Page4K) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_2M_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | mAddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else if (PageAttribute == Page1G) {
+    //
+    // Split 1G to 2M
+    // No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
+    //
+    ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
+    if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
+      NewPageEntry = PageAlloc (1);
+      DEBUG ((DEBUG_VERBOSE, "Split - 0x%x\n", NewPageEntry));
+      if (NewPageEntry == NULL) {
+        return RETURN_OUT_OF_RESOURCES;
+      }
+      BaseAddress = *PageEntry & PAGING_1G_ADDRESS_MASK_64;
+      for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
+        NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | mAddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
+      }
+      (*PageEntry) = (UINT64)(UINTN)NewPageEntry | mAddressEncMask | PAGE_ATTRIBUTE_BITS;
+      return RETURN_SUCCESS;
+    } else {
+      return RETURN_UNSUPPORTED;
+    }
+  } else {
+    return RETURN_UNSUPPORTED;
+  }
+}
+
+/**
+  This function modifies the page attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  Caller should make sure BaseAddress and Length is at page boundary.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to modify for the memory region.
+  @param[in]   IsSet            TRUE means to set attributes. FALSE means to clear attributes.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+  @param[out]  IsModified       TRUE means page table modified. FALSE means page table not modified.
+
+  @retval RETURN_SUCCESS           The attributes were modified for the memory region.
+  @retval RETURN_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                   BaseAddress and Length cannot be modified.
+  @retval RETURN_INVALID_PARAMETER Length is zero.
+                                   Attributes specified an illegal combination of attributes that
+                                   cannot be set together.
+  @retval RETURN_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                   the memory resource range.
+  @retval RETURN_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                   resource range specified by BaseAddress and Length.
+                                   The bit mask of attributes is not support for the memory resource
+                                   range specified by BaseAddress and Length.
+**/
+RETURN_STATUS
+EFIAPI
+ConvertMemoryPageAttributes (
+  IN  PHYSICAL_ADDRESS                  BaseAddress,
+  IN  UINT64                            Length,
+  IN  UINT64                            Attributes,
+  IN  BOOLEAN                           IsSet,
+  OUT BOOLEAN                           *IsSplitted,  OPTIONAL
+  OUT BOOLEAN                           *IsModified   OPTIONAL
+  )
+{
+  UINT64                            *PageEntry;
+  PAGE_ATTRIBUTE                    PageAttribute;
+  UINTN                             PageEntryLength;
+  PAGE_ATTRIBUTE                    SplitAttribute;
+  RETURN_STATUS                     Status;
+  BOOLEAN                           IsEntryModified;
+  EFI_PHYSICAL_ADDRESS              MaximumSupportMemAddress;
+
+  ASSERT (Attributes != 0);
+  ASSERT ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0);
+
+  ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
+  ASSERT ((Length & (SIZE_4KB - 1)) == 0);
+
+  if (Length == 0) {
+    return RETURN_INVALID_PARAMETER;
+  }
+
+  MaximumSupportMemAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)(LShiftU64 (1, mPhysicalAddressBits) - 1);
+  if (BaseAddress > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if (Length > MaximumSupportMemAddress) {
+    return RETURN_UNSUPPORTED;
+  }
+  if ((Length != 0) && (BaseAddress > MaximumSupportMemAddress - (Length - 1))) {
+    return RETURN_UNSUPPORTED;
+  }
+
+//  DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
+
+  if (IsSplitted != NULL) {
+    *IsSplitted = FALSE;
+  }
+  if (IsModified != NULL) {
+    *IsModified = FALSE;
+  }
+
+  //
+  // Below logic is to check 2M/4K page to make sure we do not waste memory.
+  //
+  while (Length != 0) {
+    PageEntry = GetPageTableEntry (BaseAddress, &PageAttribute);
+    if (PageEntry == NULL) {
+      return RETURN_UNSUPPORTED;
+    }
+    PageEntryLength = PageAttributeToLength (PageAttribute);
+    SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
+    if (SplitAttribute == PageNone) {
+      ConvertPageEntryAttribute (PageEntry, Attributes, IsSet, &IsEntryModified);
+      if (IsEntryModified) {
+        if (IsModified != NULL) {
+          *IsModified = TRUE;
+        }
+      }
+      //
+      // Convert success, move to next
+      //
+      BaseAddress += PageEntryLength;
+      Length -= PageEntryLength;
+    } else {
+      Status = SplitPage (PageEntry, PageAttribute, SplitAttribute);
+      if (RETURN_ERROR (Status)) {
+        return RETURN_UNSUPPORTED;
+      }
+      if (IsSplitted != NULL) {
+        *IsSplitted = TRUE;
+      }
+      if (IsModified != NULL) {
+        *IsModified = TRUE;
+      }
+      //
+      // Just split current page
+      // Convert success in next around
+      //
+    }
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  FlushTlb on current processor.
+
+  @param[in,out] Buffer  Pointer to private data buffer.
+**/
+VOID
+EFIAPI
+FlushTlbOnCurrentProcessor (
+  IN OUT VOID  *Buffer
+  )
+{
+  CpuFlushTlb ();
+}
+
+/**
+  FlushTlb for all processors.
+**/
+VOID
+FlushTlbForAll (
+  VOID
+  )
+{
+  UINTN       Index;
+
+  FlushTlbOnCurrentProcessor (NULL);
+
+  if (gSmmCoreSmst.SmmStartupThisAp == NULL) {
+    DEBUG ((DEBUG_WARN, "Cannot flush TLB for APs\r\n"));
+    return;
+  }
+
+  for (Index = 0; Index < gSmmCoreSmst.NumberOfCpus; Index++) {
+    if (Index != gSmmCoreSmst.CurrentlyExecutingCpu) {
+      // Force to start up AP in blocking mode,
+      gSmmCoreSmst.SmmStartupThisAp (FlushTlbOnCurrentProcessor, Index, NULL);
+      // Do not check return status, because AP might not be present in some corner cases.
+    }
+  }
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, TRUE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributesEx (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes,
+  OUT BOOLEAN                                    *IsSplitted  OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     IsModified;
+
+  Status = ConvertMemoryPageAttributes (BaseAddress, Length, Attributes, FALSE, IsSplitted, &IsModified);
+  if (!EFI_ERROR(Status)) {
+    if (IsModified) {
+      //
+      // Flush TLB as last step
+      //
+      FlushTlbForAll();
+    }
+  }
+
+  return Status;
+}
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to set for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmSetMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]  BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]  Length           The size in bytes of the memory region.
+  @param[in]  Attributes       The bit mask of attributes to clear for the memory region.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  )
+{
+  return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL);
+}
+
+/**
+  Initialize the Page Table lib.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  )
+{
+  mAddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
+  mPhysicalAddressBits = CalculateMaximumSupportAddress ();
+  DEBUG ((DEBUG_INFO, "mAddressEncMask      = 0x%lx\r\n", mAddressEncMask));
+  DEBUG ((DEBUG_INFO, "mPhysicalAddressBits = %d\r\n", mPhysicalAddressBits));
+  return ;
+}
+
diff --git a/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
new file mode 100644
index 0000000000..7060f38a2e
--- /dev/null
+++ b/MdeModulePkg/Core/PiSmmCore/Misc/PageTable.h
@@ -0,0 +1,174 @@
+/** @file
+  Page table management header file.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef _PAGE_TABLE_LIB_H_
+#define _PAGE_TABLE_LIB_H_
+
+///
+/// Page Table Entry
+///
+#define IA32_PG_P                   BIT0
+#define IA32_PG_RW                  BIT1
+#define IA32_PG_U                   BIT2
+#define IA32_PG_WT                  BIT3
+#define IA32_PG_CD                  BIT4
+#define IA32_PG_A                   BIT5
+#define IA32_PG_D                   BIT6
+#define IA32_PG_PS                  BIT7
+#define IA32_PG_PAT_2M              BIT12
+#define IA32_PG_PAT_4K              IA32_PG_PS
+#define IA32_PG_PMNT                BIT62
+#define IA32_PG_NX                  BIT63
+
+#define PAGE_ATTRIBUTE_BITS         (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
+//
+// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
+// X64 PAE PDPTE does not have such restriction
+//
+#define IA32_PAE_PDPTE_ATTRIBUTE_BITS    (IA32_PG_P)
+
+#define PAGE_PROGATE_BITS           (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
+
+#define PAGING_4K_MASK  0xFFF
+#define PAGING_2M_MASK  0x1FFFFF
+#define PAGING_1G_MASK  0x3FFFFFFF
+
+#define PAGING_PAE_INDEX_MASK  0x1FF
+
+#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
+#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
+#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
+
+#define SMRR_MAX_ADDRESS       BASE_4GB
+
+typedef enum {
+  PageNone = 0,
+  Page4K,
+  Page2M,
+  Page1G,
+} PAGE_ATTRIBUTE;
+
+typedef struct {
+  PAGE_ATTRIBUTE   Attribute;
+  UINT64           Length;
+  UINT64           AddressMask;
+} PAGE_ATTRIBUTE_TABLE;
+
+/**
+  Helper function to allocate pages without Guard for internal uses
+
+  @param[in]  Pages       Page number
+
+  @return Address of memory allocated
+**/
+VOID *
+PageAlloc (
+  IN UINTN  Pages
+  );
+
+/**
+  This function sets the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to set for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were set for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmSetMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  This function clears the attributes for the memory region specified by BaseAddress and
+  Length from their current attributes to the attributes specified by Attributes.
+
+  @param[in]   BaseAddress      The physical address that is the start address of a memory region.
+  @param[in]   Length           The size in bytes of the memory region.
+  @param[in]   Attributes       The bit mask of attributes to clear for the memory region.
+  @param[out]  IsSplitted       TRUE means page table splitted. FALSE means page table not splitted.
+
+  @retval EFI_SUCCESS           The attributes were cleared for the memory region.
+  @retval EFI_ACCESS_DENIED     The attributes for the memory resource range specified by
+                                BaseAddress and Length cannot be modified.
+  @retval EFI_INVALID_PARAMETER Length is zero.
+                                Attributes specified an illegal combination of attributes that
+                                cannot be set together.
+  @retval EFI_OUT_OF_RESOURCES  There are not enough system resources to modify the attributes of
+                                the memory resource range.
+  @retval EFI_UNSUPPORTED       The processor does not support one or more bytes of the memory
+                                resource range specified by BaseAddress and Length.
+                                The bit mask of attributes is not support for the memory resource
+                                range specified by BaseAddress and Length.
+
+**/
+EFI_STATUS
+EFIAPI
+SmmClearMemoryAttributes (
+  IN  EFI_PHYSICAL_ADDRESS                       BaseAddress,
+  IN  UINT64                                     Length,
+  IN  UINT64                                     Attributes
+  );
+
+/**
+  Initialize globals for the Page Table operation.
+**/
+VOID
+InitializePageTableGlobals (
+  VOID
+  );
+
+/**
+  Return page table base.
+
+  @return page table base.
+**/
+UINTN
+GetPageTableBase (
+  VOID
+  );
+
+/**
+  Return page table entry to match the address.
+
+  @param[in]   Address          The address to be checked.
+  @param[out]  PageAttributes   The page attribute of the page entry.
+
+  @return The page entry.
+**/
+VOID *
+GetPageTableEntry (
+  IN  PHYSICAL_ADDRESS                  Address,
+  OUT PAGE_ATTRIBUTE                    *PageAttribute
+  );
+
+#endif
diff --git a/MdeModulePkg/Core/PiSmmCore/Page.c b/MdeModulePkg/Core/PiSmmCore/Page.c
index 4154c2e6a1..e0f0046c20 100644
--- a/MdeModulePkg/Core/PiSmmCore/Page.c
+++ b/MdeModulePkg/Core/PiSmmCore/Page.c
@@ -64,6 +64,8 @@ LIST_ENTRY   mFreeMemoryMapEntryList = INITIALIZE_LIST_HEAD_VARIABLE (mFreeMemor
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -77,7 +79,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   );

 /**
@@ -112,7 +115,8 @@ AllocateMemoryMapEntry (
                EfiRuntimeServicesData,
                EFI_SIZE_TO_PAGES (RUNTIME_PAGE_ALLOCATION_GRANULARITY),
                &Mem,
-               TRUE
+               TRUE,
+               FALSE
                );
     ASSERT_EFI_ERROR (Status);
     if(!EFI_ERROR (Status)) {
@@ -688,6 +692,8 @@ InternalAllocAddress (
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
   @param[in]   AddRegion              If this memory is new added region.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -701,7 +707,8 @@ SmmInternalAllocatePagesEx (
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
   OUT EFI_PHYSICAL_ADDRESS  *Memory,
-  IN  BOOLEAN               AddRegion
+  IN  BOOLEAN               AddRegion,
+  IN  BOOLEAN               NeedGuard
   )
 {
   UINTN  RequestedAddress;
@@ -723,6 +730,21 @@ SmmInternalAllocatePagesEx (
     case AllocateAnyPages:
       RequestedAddress = (UINTN)(-1);
     case AllocateMaxAddress:
+      if (NeedGuard) {
+        *Memory = InternalAllocMaxAddressWithGuard (
+                      &mSmmMemoryMap,
+                      NumberOfPages,
+                      RequestedAddress,
+                      MemoryType
+                      );
+        if (*Memory == (UINTN)-1) {
+          return EFI_OUT_OF_RESOURCES;
+        } else {
+          ASSERT (VerifyMemoryGuard (*Memory, NumberOfPages) == TRUE);
+          return EFI_SUCCESS;
+        }
+      }
+
       *Memory = InternalAllocMaxAddress (
                   &mSmmMemoryMap,
                   NumberOfPages,
@@ -766,6 +788,8 @@ SmmInternalAllocatePagesEx (
   @param[in]   NumberOfPages          The number of pages to allocate.
   @param[out]  Memory                 A pointer to receive the base allocated memory
                                       address.
+  @param[in]   NeedGuard              Flag to indicate Guard page is needed
+                                      or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -779,10 +803,12 @@ SmmInternalAllocatePages (
   IN  EFI_ALLOCATE_TYPE     Type,
   IN  EFI_MEMORY_TYPE       MemoryType,
   IN  UINTN                 NumberOfPages,
-  OUT EFI_PHYSICAL_ADDRESS  *Memory
+  OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN  BOOLEAN               NeedGuard
   )
 {
-  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory, FALSE);
+  return SmmInternalAllocatePagesEx (Type, MemoryType, NumberOfPages, Memory,
+                                     FALSE, NeedGuard);
 }

 /**
@@ -811,8 +837,11 @@ SmmAllocatePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     NeedGuard;

-  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory);
+  NeedGuard = IsPageTypeToGuard (MemoryType, Type);
+  Status = SmmInternalAllocatePages (Type, MemoryType, NumberOfPages, Memory,
+                                     NeedGuard);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
@@ -941,9 +970,13 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN EFI_PHYSICAL_ADDRESS  Memory,
-  IN UINTN                 NumberOfPages
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               IsGuarded
   )
 {
+  if (IsGuarded) {
+    return SmmInternalFreePagesExWithGuard (Memory, NumberOfPages, FALSE);
+  }
   return SmmInternalFreePagesEx (Memory, NumberOfPages, FALSE);
 }

@@ -966,8 +999,10 @@ SmmFreePages (
   )
 {
   EFI_STATUS  Status;
+  BOOLEAN     IsGuarded;

-  Status = SmmInternalFreePages (Memory, NumberOfPages);
+  IsGuarded = IsHeapGuardEnabled () && IsMemoryGuarded (Memory);
+  Status = SmmInternalFreePages (Memory, NumberOfPages, IsGuarded);
   if (!EFI_ERROR (Status)) {
     SmmCoreUpdateProfile (
       (EFI_PHYSICAL_ADDRESS) (UINTN) RETURN_ADDRESS (0),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
index 9e4390e15a..5c1d5a5306 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.c
@@ -451,6 +451,11 @@ SmmEntryPoint (
   //
   PlatformHookBeforeSmmDispatch ();

+  //
+  // Call memory management hook function
+  //
+  SmmEntryPointMemoryManagementHook ();
+
   //
   // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
   //
@@ -644,7 +649,12 @@ SmmMain (
   //
   gSmmCorePrivate->Smst          = &gSmmCoreSmst;
   gSmmCorePrivate->SmmEntryPoint = SmmEntryPoint;
-
+
+  //
+  // Initialize globals for page table operations
+  //
+  InitializePageTableGlobals ();
+
   //
   // No need to initialize memory service.
   // It is done in constructor of PiSmmCoreMemoryAllocationLib(),
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
index b6f815c68d..8c61fdcf0c 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
@@ -59,6 +59,7 @@
 #include <Library/SmmMemLib.h>

 #include "PiSmmCorePrivateData.h"
+#include "Misc/HeapGuard.h"

 //
 // Used to build a table of SMI Handlers that the SMM Core registers
@@ -317,6 +318,7 @@ SmmAllocatePages (
   @param  NumberOfPages          The number of pages to allocate
   @param  Memory                 A pointer to receive the base allocated memory
                                  address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not

   @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in spec.
   @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
@@ -330,7 +332,8 @@ SmmInternalAllocatePages (
   IN      EFI_ALLOCATE_TYPE         Type,
   IN      EFI_MEMORY_TYPE           MemoryType,
   IN      UINTN                     NumberOfPages,
-  OUT     EFI_PHYSICAL_ADDRESS      *Memory
+  OUT     EFI_PHYSICAL_ADDRESS      *Memory,
+  IN      BOOLEAN                   NeedGuard
   );

 /**
@@ -356,6 +359,8 @@ SmmFreePages (

   @param  Memory                 Base address of memory being freed
   @param  NumberOfPages          The number of pages to free
+  @param  IsGuarded              Flag to indicate if the memory is guarded
+                                 or not

   @retval EFI_NOT_FOUND          Could not find the entry that covers the range
   @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
@@ -366,7 +371,8 @@ EFI_STATUS
 EFIAPI
 SmmInternalFreePages (
   IN      EFI_PHYSICAL_ADDRESS      Memory,
-  IN      UINTN                     NumberOfPages
+  IN      UINTN                     NumberOfPages,
+  IN      BOOLEAN                   IsGuarded
   );

 /**
@@ -1231,4 +1237,74 @@ typedef enum {

 extern LIST_ENTRY  mSmmPoolLists[SmmPoolTypeMax][MAX_POOL_INDEX];

+/**
+  Internal Function. Allocate n pages from given free page node.
+
+  @param  Pages                  The free page node.
+  @param  NumberOfPages          Number of pages to be allocated.
+  @param  MaxAddress             Request to allocate memory below this address.
+
+  @return Memory address of allocated pages.
+
+**/
+UINTN
+InternalAllocPagesOnOneNode (
+  IN OUT FREE_PAGE_LIST   *Pages,
+  IN     UINTN            NumberOfPages,
+  IN     UINTN            MaxAddress
+  );
+
+/**
+  Update SMM memory map entry.
+
+  @param[in]  Type                   The type of allocation to perform.
+  @param[in]  Memory                 The base of memory address.
+  @param[in]  NumberOfPages          The number of pages to allocate.
+  @param[in]  AddRegion              If this memory is new added region.
+**/
+VOID
+ConvertSmmMemoryMapEntry (
+  IN EFI_MEMORY_TYPE       Type,
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Internal function.  Moves any memory descriptors that are on the
+  temporary descriptor stack to heap.
+
+**/
+VOID
+CoreFreeMemoryMapStack (
+  VOID
+  );
+
+/**
+  Frees previous allocated pages.
+
+  @param[in]  Memory                 Base address of memory being freed.
+  @param[in]  NumberOfPages          The number of pages to free.
+  @param[in]  AddRegion              If this memory is new added region.
+
+  @retval EFI_NOT_FOUND          Could not find the entry that covers the range.
+  @retval EFI_INVALID_PARAMETER  Address not aligned, Address is zero or NumberOfPages is zero.
+  @return EFI_SUCCESS            Pages successfully freed.
+
+**/
+EFI_STATUS
+SmmInternalFreePagesEx (
+  IN EFI_PHYSICAL_ADDRESS  Memory,
+  IN UINTN                 NumberOfPages,
+  IN BOOLEAN               AddRegion
+  );
+
+/**
+  Hook function used to set all Guard pages after entering SMM mode
+**/
+VOID
+SmmEntryPointMemoryManagementHook (
+  VOID
+  );
+
 #endif
diff --git a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
index 49ae6fbb57..e505b165bc 100644
--- a/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
+++ b/MdeModulePkg/Core/PiSmmCore/PiSmmCore.inf
@@ -40,6 +40,8 @@
   SmramProfileRecord.c
   MemoryAttributesTable.c
   SmiHandlerProfile.c
+  Misc/HeapGuard.c
+  Misc/PageTable.c

 [Packages]
   MdePkg/MdePkg.dec
@@ -65,6 +67,7 @@
   HobLib
   SmmMemLib
   DxeServicesLib
+  CpuLib

 [Protocols]
   gEfiDxeSmmReadyToLockProtocolGuid             ## UNDEFINED # SmiHandlerRegister
@@ -88,6 +91,7 @@
   gEfiSmmGpiDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
   gEfiSmmIoTrapDispatch2ProtocolGuid            ## SOMETIMES_CONSUMES
   gEfiSmmUsbDispatch2ProtocolGuid               ## SOMETIMES_CONSUMES
+  gEfiSmmCpuProtocolGuid                        ## SOMETIMES_CONSUMES

 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdLoadFixAddressSmmCodePageNumber     ## SOMETIMES_CONSUMES
@@ -96,6 +100,10 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfilePropertyMask           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMemoryProfileDriverPath             ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdSmiHandlerProfilePropertyMask       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType                   ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES

 [Guids]
   gAprioriGuid                                  ## SOMETIMES_CONSUMES   ## File
diff --git a/MdeModulePkg/Core/PiSmmCore/Pool.c b/MdeModulePkg/Core/PiSmmCore/Pool.c
index 36317563c4..cecad65cc3 100644
--- a/MdeModulePkg/Core/PiSmmCore/Pool.c
+++ b/MdeModulePkg/Core/PiSmmCore/Pool.c
@@ -144,7 +144,9 @@ InternalAllocPoolByIndex (
   Status = EFI_SUCCESS;
   Hdr = NULL;
   if (PoolIndex == MAX_POOL_INDEX) {
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1), &Address);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType,
+                                       EFI_SIZE_TO_PAGES (MAX_POOL_SIZE << 1),
+                                       &Address, FALSE);
     if (EFI_ERROR (Status)) {
       return EFI_OUT_OF_RESOURCES;
     }
@@ -243,6 +245,9 @@ SmmInternalAllocatePool (
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  Address;
   UINTN                 PoolIndex;
+  BOOLEAN               HasPoolTail;
+  BOOLEAN               NeedGuard;
+  UINTN                 NoPages;

   Address = 0;

@@ -251,25 +256,43 @@ SmmInternalAllocatePool (
     return EFI_INVALID_PARAMETER;
   }

+  NeedGuard   = IsPoolTypeToGuard (PoolType);
+  HasPoolTail = !(NeedGuard &&
+                  ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   //
   // Adjust the size by the pool header & tail overhead
   //
   Size += POOL_OVERHEAD;
-  if (Size > MAX_POOL_SIZE) {
-    Size = EFI_SIZE_TO_PAGES (Size);
-    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, Size, &Address);
+  if (Size > MAX_POOL_SIZE || NeedGuard) {
+    if (!HasPoolTail) {
+      Size -= sizeof (POOL_TAIL);
+    }
+
+    NoPages = EFI_SIZE_TO_PAGES (Size);
+    Status = SmmInternalAllocatePages (AllocateAnyPages, PoolType, NoPages,
+                                       &Address, NeedGuard);
     if (EFI_ERROR (Status)) {
       return Status;
     }

+    if (NeedGuard) {
+      ASSERT (VerifyMemoryGuard (Address, NoPages) == TRUE);
+      Address = (EFI_PHYSICAL_ADDRESS)AdjustPoolHeadA (Address, NoPages, Size);
+    }
+
     PoolHdr = (POOL_HEADER*)(UINTN)Address;
     PoolHdr->Signature = POOL_HEAD_SIGNATURE;
-    PoolHdr->Size = EFI_PAGES_TO_SIZE (Size);
+    PoolHdr->Size = Size;
     PoolHdr->Available = FALSE;
     PoolHdr->Type = PoolType;
-    PoolTail = HEAD_TO_TAIL(PoolHdr);
-    PoolTail->Signature = POOL_TAIL_SIGNATURE;
-    PoolTail->Size = PoolHdr->Size;
+
+    if (HasPoolTail) {
+      PoolTail = HEAD_TO_TAIL (PoolHdr);
+      PoolTail->Signature = POOL_TAIL_SIGNATURE;
+      PoolTail->Size = PoolHdr->Size;
+    }
+
     *Buffer = PoolHdr + 1;
     return Status;
   }
@@ -341,28 +364,45 @@ SmmInternalFreePool (
 {
   FREE_POOL_HEADER  *FreePoolHdr;
   POOL_TAIL         *PoolTail;
+  BOOLEAN           HasPoolTail;
+  BOOLEAN           MemoryGuarded;

   if (Buffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }

+  MemoryGuarded = IsHeapGuardEnabled () &&
+                  IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer);
+  HasPoolTail   = !(MemoryGuarded &&
+                    ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));
+
   FreePoolHdr = (FREE_POOL_HEADER*)((POOL_HEADER*)Buffer - 1);
   ASSERT (FreePoolHdr->Header.Signature == POOL_HEAD_SIGNATURE);
   ASSERT (!FreePoolHdr->Header.Available);
-  PoolTail = HEAD_TO_TAIL(&FreePoolHdr->Header);
-  ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
-  ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
-
   if (FreePoolHdr->Header.Signature != POOL_HEAD_SIGNATURE) {
     return EFI_INVALID_PARAMETER;
   }

-  if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
-    return EFI_INVALID_PARAMETER;
+  if (HasPoolTail) {
+    PoolTail = HEAD_TO_TAIL (&FreePoolHdr->Header);
+    ASSERT (PoolTail->Signature == POOL_TAIL_SIGNATURE);
+    ASSERT (FreePoolHdr->Header.Size == PoolTail->Size);
+    if (PoolTail->Signature != POOL_TAIL_SIGNATURE) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (FreePoolHdr->Header.Size != PoolTail->Size) {
+      return EFI_INVALID_PARAMETER;
+    }
   }

-  if (FreePoolHdr->Header.Size != PoolTail->Size) {
-    return EFI_INVALID_PARAMETER;
+  if (MemoryGuarded) {
+    Buffer = AdjustPoolHeadF ((EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr);
+    return SmmInternalFreePages (
+             (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer,
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             TRUE
+             );
   }

   if (FreePoolHdr->Header.Size > MAX_POOL_SIZE) {
@@ -370,7 +410,8 @@ SmmInternalFreePool (
     ASSERT ((FreePoolHdr->Header.Size & EFI_PAGE_MASK) == 0);
     return SmmInternalFreePages (
              (EFI_PHYSICAL_ADDRESS)(UINTN)FreePoolHdr,
-             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size)
+             EFI_SIZE_TO_PAGES (FreePoolHdr->Header.Size),
+             FALSE
              );
   }
   return InternalFreePoolByIndex (FreePoolHdr, PoolTail);
--
2.14.1.windows.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2017-10-20  1:45 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-10-17 13:29 [PATCH v2 0/6] Implement heap guard feature Jian J Wang
2017-10-17 13:29 ` [PATCH v2 1/6] MdeModulePkg/DxeCore: Implement heap guard feature for UEFI Jian J Wang
2017-10-17 13:29 ` [PATCH v2 2/6] MdeModulePkg/PiSmmCore: Implement heap guard feature for SMM mode Jian J Wang
2017-10-18  5:07   ` Yao, Jiewen
2017-10-18  5:51     ` Wang, Jian J
2017-10-18  5:54       ` Yao, Jiewen
2017-10-20  0:54         ` Wang, Jian J
2017-10-20  1:36           ` Yao, Jiewen
2017-10-20  1:49             ` Wang, Jian J
2017-10-17 13:29 ` [PATCH v2 3/6] MdeModulePkg/MdeModulePkg.dec, .uni: Add heap guard related PCDs and string tokens Jian J Wang
2017-10-17 13:29 ` [PATCH v2 4/6] UefiCpuPkg/CpuDxe: Reduce debug message Jian J Wang
2017-10-17 13:29 ` [PATCH v2 5/6] UefiCpuPkg/PiSmmCpuDxeSmm: Disable page table protection Jian J Wang
2017-10-17 13:29 ` [PATCH v2 6/6] MdeModulePkg/DxeIpl: Enable paging for heap guard Jian J Wang

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