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From: "Lendacky, Thomas" <thomas.lendacky@amd.com>
To: devel@edk2.groups.io
Cc: Jordan Justen <jordan.l.justen@intel.com>,
	Laszlo Ersek <lersek@redhat.com>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	Michael D Kinney <michael.d.kinney@intel.com>,
	Liming Gao <liming.gao@intel.com>,
	Eric Dong <eric.dong@intel.com>, Ray Ni <ray.ni@intel.com>,
	Brijesh Singh <brijesh.singh@amd.com>,
	Jian J Wang <jian.j.wang@intel.com>,
	Hao A Wu <hao.a.wu@intel.com>, Dandan Bi <dandan.bi@intel.com>
Subject: [PATCH v5 04/42] MdeModulePkg/DxeIplPeim: Support GHCB pages when creating page tables
Date: Mon,  2 Mar 2020 17:06:35 -0600	[thread overview]
Message-ID: <6a0093d46b49995840f2922826a257717e8893f7.1583190432.git.thomas.lendacky@amd.com> (raw)
In-Reply-To: <cover.1583190432.git.thomas.lendacky@amd.com>

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198

GHCB pages must be mapped as shared pages, so modify the process of
creating identity mapped pagetable entries so that GHCB entries are
created without the encryption bit set.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf       |  2 +
 .../Core/DxeIplPeim/X64/VirtualMemory.h       | 12 ++++-
 .../Core/DxeIplPeim/Ia32/DxeLoadFunc.c        |  4 +-
 .../Core/DxeIplPeim/X64/DxeLoadFunc.c         | 11 ++++-
 .../Core/DxeIplPeim/X64/VirtualMemory.c       | 49 ++++++++++++++-----
 5 files changed, 62 insertions(+), 16 deletions(-)

diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
index 98bc17fc9d1f..5e6b78e295e6 100644
--- a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
@@ -111,6 +111,8 @@ [Pcd.IA32,Pcd.X64]
   gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdCpuStackGuard                       ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdUse5LevelPageTable                  ## SOMETIMES_CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdGhcbBase                            ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdGhcbSize                            ## CONSUMES
 
 [Pcd.IA32,Pcd.X64,Pcd.ARM,Pcd.AARCH64]
   gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack               ## SOMETIMES_CONSUMES
diff --git a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h
index 2d0493f109e8..6b7c38a441d6 100644
--- a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h
+++ b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h
@@ -201,6 +201,8 @@ EnableExecuteDisableBit (
   @param[in, out] PageEntry2M           Pointer to 2M page entry.
   @param[in]      StackBase             Stack base address.
   @param[in]      StackSize             Stack size.
+  @param[in]      GhcbBase              GHCB page area base address.
+  @param[in]      GhcbSize              GHCB page area size.
 
 **/
 VOID
@@ -208,7 +210,9 @@ Split2MPageTo4K (
   IN EFI_PHYSICAL_ADDRESS               PhysicalAddress,
   IN OUT UINT64                         *PageEntry2M,
   IN EFI_PHYSICAL_ADDRESS               StackBase,
-  IN UINTN                              StackSize
+  IN UINTN                              StackSize,
+  IN EFI_PHYSICAL_ADDRESS               GhcbBase,
+  IN UINTN                              GhcbSize
   );
 
 /**
@@ -217,6 +221,8 @@ Split2MPageTo4K (
 
   @param[in] StackBase  Stack base address.
   @param[in] StackSize  Stack size.
+  @param[in] GhcbBase   GHCB page area base address.
+  @param[in] GhcbSize   GHCB page area size.
 
   @return The address of 4 level page map.
 
@@ -224,7 +230,9 @@ Split2MPageTo4K (
 UINTN
 CreateIdentityMappingPageTables (
   IN EFI_PHYSICAL_ADDRESS   StackBase,
-  IN UINTN                  StackSize
+  IN UINTN                  StackSize,
+  IN EFI_PHYSICAL_ADDRESS   GhcbBase,
+  IN UINTN                  GhcbkSize
   );
 
 
diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index 6e8ca824d469..284b34818ca7 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -123,7 +123,7 @@ Create4GPageTablesIa32Pae (
         //
         // Need to split this 2M page that covers stack range.
         //
-        Split2MPageTo4K (PhysicalAddress, (UINT64 *) PageDirectoryEntry, StackBase, StackSize);
+        Split2MPageTo4K (PhysicalAddress, (UINT64 *) PageDirectoryEntry, StackBase, StackSize, 0, 0);
       } else {
         //
         // Fill in the Page Directory entries
@@ -282,7 +282,7 @@ HandOffToDxeCore (
     //
     // Create page table and save PageMapLevel4 to CR3
     //
-    PageTables = CreateIdentityMappingPageTables (BaseOfStack, STACK_SIZE);
+    PageTables = CreateIdentityMappingPageTables (BaseOfStack, STACK_SIZE, 0, 0);
 
     //
     // End of PEI phase signal
diff --git a/MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c
index f465eb1d8ac4..156a477d8467 100644
--- a/MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c
@@ -35,6 +35,8 @@ HandOffToDxeCore (
   UINT32                          Index;
   EFI_VECTOR_HANDOFF_INFO         *VectorInfo;
   EFI_PEI_VECTOR_HANDOFF_INFO_PPI *VectorHandoffInfoPpi;
+  VOID                            *GhcbBase;
+  UINTN                           GhcbSize;
 
   //
   // Clear page 0 and mark it as allocated if NULL pointer detection is enabled.
@@ -81,12 +83,19 @@ HandOffToDxeCore (
   TopOfStack = (VOID *) ((UINTN) BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);
   TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
 
+  //
+  // Get the address and size of the GHCB pages
+  //
+  GhcbBase = (VOID *) PcdGet64 (PcdGhcbBase);
+  GhcbSize = PcdGet64 (PcdGhcbSize);
+
   PageTables = 0;
   if (FeaturePcdGet (PcdDxeIplBuildPageTables)) {
     //
     // Create page table and save PageMapLevel4 to CR3
     //
-    PageTables = CreateIdentityMappingPageTables ((EFI_PHYSICAL_ADDRESS) (UINTN) BaseOfStack, STACK_SIZE);
+    PageTables = CreateIdentityMappingPageTables ((EFI_PHYSICAL_ADDRESS) (UINTN) BaseOfStack, STACK_SIZE,
+                                                  (EFI_PHYSICAL_ADDRESS) (UINTN) GhcbBase, GhcbSize);
   } else {
     //
     // Set NX for stack feature also require PcdDxeIplBuildPageTables be TRUE
diff --git a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
index 516cf908bc88..32a81d1f3c21 100644
--- a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
+++ b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
@@ -181,6 +181,8 @@ EnableExecuteDisableBit (
   @param Size         Size of the given physical memory.
   @param StackBase    Base address of stack.
   @param StackSize    Size of stack.
+  @param GhcbBase     Base address of GHCB pages.
+  @param GhcbSize     Size of GHCB area.
 
   @retval TRUE      Page table should be split.
   @retval FALSE     Page table should not be split.
@@ -190,7 +192,9 @@ ToSplitPageTable (
   IN EFI_PHYSICAL_ADDRESS               Address,
   IN UINTN                              Size,
   IN EFI_PHYSICAL_ADDRESS               StackBase,
-  IN UINTN                              StackSize
+  IN UINTN                              StackSize,
+  IN EFI_PHYSICAL_ADDRESS               GhcbBase,
+  IN UINTN                              GhcbSize
   )
 {
   if (IsNullDetectionEnabled () && Address == 0) {
@@ -209,6 +213,12 @@ ToSplitPageTable (
     }
   }
 
+  if (GhcbBase) {
+    if ((Address < GhcbBase + GhcbSize) && ((Address + Size) > GhcbBase)) {
+      return TRUE;
+    }
+  }
+
   return FALSE;
 }
 /**
@@ -322,6 +332,8 @@ AllocatePageTableMemory (
   @param[in, out] PageEntry2M           Pointer to 2M page entry.
   @param[in]      StackBase             Stack base address.
   @param[in]      StackSize             Stack size.
+  @param[in]      GhcbBase              GHCB page area base address.
+  @param[in]      GhcbSize              GHCB page area size.
 
 **/
 VOID
@@ -329,7 +341,9 @@ Split2MPageTo4K (
   IN EFI_PHYSICAL_ADDRESS               PhysicalAddress,
   IN OUT UINT64                         *PageEntry2M,
   IN EFI_PHYSICAL_ADDRESS               StackBase,
-  IN UINTN                              StackSize
+  IN UINTN                              StackSize,
+  IN EFI_PHYSICAL_ADDRESS               GhcbBase,
+  IN UINTN                              GhcbSize
   )
 {
   EFI_PHYSICAL_ADDRESS                  PhysicalAddress4K;
@@ -355,7 +369,12 @@ Split2MPageTo4K (
     //
     // Fill in the Page Table entries
     //
-    PageTableEntry->Uint64 = (UINT64) PhysicalAddress4K | AddressEncMask;
+    PageTableEntry->Uint64 = (UINT64) PhysicalAddress4K;
+    if (!GhcbBase
+        || (PhysicalAddress4K < GhcbBase)
+        || (PhysicalAddress4K >= GhcbBase + GhcbSize)) {
+      PageTableEntry->Uint64 |= AddressEncMask;
+    }
     PageTableEntry->Bits.ReadWrite = 1;
 
     if ((IsNullDetectionEnabled () && PhysicalAddress4K == 0) ||
@@ -383,6 +402,8 @@ Split2MPageTo4K (
   @param[in, out] PageEntry1G           Pointer to 1G page entry.
   @param[in]      StackBase             Stack base address.
   @param[in]      StackSize             Stack size.
+  @param[in]      GhcbBase              GHCB page area base address.
+  @param[in]      GhcbSize              GHCB page area size.
 
 **/
 VOID
@@ -390,7 +411,9 @@ Split1GPageTo2M (
   IN EFI_PHYSICAL_ADDRESS               PhysicalAddress,
   IN OUT UINT64                         *PageEntry1G,
   IN EFI_PHYSICAL_ADDRESS               StackBase,
-  IN UINTN                              StackSize
+  IN UINTN                              StackSize,
+  IN EFI_PHYSICAL_ADDRESS               GhcbBase,
+  IN UINTN                              GhcbSize
   )
 {
   EFI_PHYSICAL_ADDRESS                  PhysicalAddress2M;
@@ -413,11 +436,11 @@ Split1GPageTo2M (
 
   PhysicalAddress2M = PhysicalAddress;
   for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectoryEntry++, PhysicalAddress2M += SIZE_2MB) {
-    if (ToSplitPageTable (PhysicalAddress2M, SIZE_2MB, StackBase, StackSize)) {
+    if (ToSplitPageTable (PhysicalAddress2M, SIZE_2MB, StackBase, StackSize, GhcbBase, GhcbSize)) {
       //
       // Need to split this 2M page that covers NULL or stack range.
       //
-      Split2MPageTo4K (PhysicalAddress2M, (UINT64 *) PageDirectoryEntry, StackBase, StackSize);
+      Split2MPageTo4K (PhysicalAddress2M, (UINT64 *) PageDirectoryEntry, StackBase, StackSize, GhcbBase, GhcbSize);
     } else {
       //
       // Fill in the Page Directory entries
@@ -616,6 +639,8 @@ EnablePageTableProtection (
 
   @param[in] StackBase  Stack base address.
   @param[in] StackSize  Stack size.
+  @param[in] GhcbBase   GHCB base address.
+  @param[in] GhcbSize   GHCB size.
 
   @return The address of 4 level page map.
 
@@ -623,7 +648,9 @@ EnablePageTableProtection (
 UINTN
 CreateIdentityMappingPageTables (
   IN EFI_PHYSICAL_ADDRESS   StackBase,
-  IN UINTN                  StackSize
+  IN UINTN                  StackSize,
+  IN EFI_PHYSICAL_ADDRESS   GhcbBase,
+  IN UINTN                  GhcbSize
   )
 {
   UINT32                                        RegEax;
@@ -809,8 +836,8 @@ CreateIdentityMappingPageTables (
         PageDirectory1GEntry = (VOID *) PageDirectoryPointerEntry;
 
         for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectory1GEntry++, PageAddress += SIZE_1GB) {
-          if (ToSplitPageTable (PageAddress, SIZE_1GB, StackBase, StackSize)) {
-            Split1GPageTo2M (PageAddress, (UINT64 *) PageDirectory1GEntry, StackBase, StackSize);
+          if (ToSplitPageTable (PageAddress, SIZE_1GB, StackBase, StackSize, GhcbBase, GhcbSize)) {
+            Split1GPageTo2M (PageAddress, (UINT64 *) PageDirectory1GEntry, StackBase, StackSize, GhcbBase, GhcbSize);
           } else {
             //
             // Fill in the Page Directory entries
@@ -840,11 +867,11 @@ CreateIdentityMappingPageTables (
           PageDirectoryPointerEntry->Bits.Present = 1;
 
           for (IndexOfPageDirectoryEntries = 0; IndexOfPageDirectoryEntries < 512; IndexOfPageDirectoryEntries++, PageDirectoryEntry++, PageAddress += SIZE_2MB) {
-            if (ToSplitPageTable (PageAddress, SIZE_2MB, StackBase, StackSize)) {
+            if (ToSplitPageTable (PageAddress, SIZE_2MB, StackBase, StackSize, GhcbBase, GhcbSize)) {
               //
               // Need to split this 2M page that covers NULL or stack range.
               //
-              Split2MPageTo4K (PageAddress, (UINT64 *) PageDirectoryEntry, StackBase, StackSize);
+              Split2MPageTo4K (PageAddress, (UINT64 *) PageDirectoryEntry, StackBase, StackSize, GhcbBase, GhcbSize);
             } else {
               //
               // Fill in the Page Directory entries
-- 
2.17.1


  parent reply	other threads:[~2020-03-02 23:07 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-02 23:06 [PATCH v5 00/42] SEV-ES guest support Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 01/42] MdePkg: Create PCDs to be used in support of SEV-ES Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 02/42] MdePkg: Add the MSR definition for the GHCB register Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 03/42] MdePkg: Add a structure definition for the GHCB Lendacky, Thomas
2020-03-02 23:06 ` Lendacky, Thomas [this message]
2020-03-02 23:06 ` [PATCH v5 05/42] MdePkg/BaseLib: Add support for the XGETBV instruction Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 06/42] MdePkg/BaseLib: Add support for the VMGEXIT instruction Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 07/42] UefiCpuPkg: Implement library support for VMGEXIT Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 08/42] OvmfPkg: Prepare OvmfPkg to use the VmgExitLib library Lendacky, Thomas
2020-03-03 12:10   ` [edk2-devel] " Laszlo Ersek
2020-03-02 23:06 ` [PATCH v5 09/42] UefiPayloadPkg: Prepare UefiPayloadPkg " Lendacky, Thomas
2020-03-03 23:52   ` [edk2-devel] " Guo Dong
2020-03-02 23:06 ` [PATCH v5 10/42] UefiCpuPkg/CpuExceptionHandler: Add base support for the #VC exception Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 11/42] UefiCpuPkg/CpuExceptionHandler: Add support for IOIO_PROT NAE events Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 12/42] UefiCpuPkg/CpuExceptionHandler: Support string IO " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 13/42] UefiCpuPkg/CpuExceptionHandler: Add support for CPUID " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 14/42] UefiCpuPkg/CpuExceptionHandler: Add support for MSR_PROT " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 15/42] UefiCpuPkg/CpuExceptionHandler: Add support for NPF NAE events (MMIO) Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 16/42] UefiCpuPkg/CpuExceptionHandler: Add support for WBINVD NAE events Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 17/42] UefiCpuPkg/CpuExceptionHandler: Add support for RDTSC " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 18/42] UefiCpuPkg/CpuExceptionHandler: Add support for RDPMC " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 19/42] UefiCpuPkg/CpuExceptionHandler: Add support for INVD " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 20/42] UefiCpuPkg/CpuExceptionHandler: Add support for VMMCALL " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 21/42] UefiCpuPkg/CpuExceptionHandler: Add support for RDTSCP " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 22/42] UefiCpuPkg/CpuExceptionHandler: Add support for MONITOR/MONITORX " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 23/42] UefiCpuPkg/CpuExceptionHandler: Add support for MWAIT/MWAITX " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 24/42] UefiCpuPkg/CpuExceptionHandler: Add support for DR7 Read/Write " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 25/42] OvmfPkg/MemEncryptSevLib: Add an SEV-ES guest indicator function Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 26/42] OvmfPkg: Add support to perform SEV-ES initialization Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 27/42] OvmfPkg: Create a GHCB page for use during Sec phase Lendacky, Thomas
2020-03-03  5:29   ` Lendacky, Thomas
2020-03-03  5:36   ` [PATCH v5.1 27/43] " Lendacky, Thomas
2020-03-02 23:06 ` [PATCH v5 28/42] OvmfPkg/PlatformPei: Reserve GHCB-related areas if S3 is supported Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 29/42] OvmfPkg: Create GHCB pages for use during Pei and Dxe phase Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 30/42] OvmfPkg/PlatformPei: Move early GDT into ram when SEV-ES is enabled Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 31/42] UefiCpuPkg: Create an SEV-ES workarea PCD Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 32/42] OvmfPkg: Reserve a page in memory for the SEV-ES usage Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 33/42] OvmfPkg/ResetVector: Add support for a 32-bit SEV check Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 34/42] OvmfPkg/Sec: Add #VC exception handling for Sec phase Lendacky, Thomas
2020-03-03 13:29   ` [edk2-devel] " Laszlo Ersek
2020-03-03 14:20     ` Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 35/42] OvmfPkg/Sec: Enable cache early to speed up booting Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 36/42] OvmfPkg/QemuFlashFvbServicesRuntimeDxe: Bypass flash detection with SEV-ES is enabled Lendacky, Thomas
2020-03-03 12:33   ` [edk2-devel] " Laszlo Ersek
2020-03-03 14:26     ` Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 37/42] UefiCpuPkg: Add a 16-bit protected mode code segment descriptor Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 38/42] UefiCpuPkg/MpInitLib: Add CPU MP data flag to indicate if SEV-ES is enabled Lendacky, Thomas
2020-03-02 23:07 ` [PATCH v5 39/42] UefiCpuPkg: Allow AP booting under SEV-ES Lendacky, Thomas
2020-03-03  5:43 ` [PATCH v5 40/42] OvmfPkg: Use the SEV-ES work area for the SEV-ES AP reset vector Lendacky, Thomas
2020-03-03  5:43 ` [PATCH v5 41/42] OvmfPkg: Move the GHCB allocations into reserved memory Lendacky, Thomas
2020-03-03  5:43 ` [PATCH v5 42/42] UefiCpuPkg/MpInitLib: Prepare SEV-ES guest APs for OS use Lendacky, Thomas

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