Re: [PATCH v4 3/8] UefiCpuPkg/CpuDxe: Support parsing 5-level page table

["Dong, Eric" <eric.dong@intel.com>]

Reviewed-by: Eric Dong <eric.dong@intel.com>

> -----Original Message-----
> From: Ni, Ray
> Sent: Thursday, August 1, 2019 5:58 PM
> To: devel@edk2.groups.io
> Cc: Dong, Eric <eric.dong@intel.com>; Laszlo Ersek <lersek@redhat.com>
> Subject: [PATCH v4 3/8] UefiCpuPkg/CpuDxe: Support parsing 5-level page
> table
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2008
> 
> Signed-off-by: Ray Ni <ray.ni@intel.com>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> ---
>  UefiCpuPkg/CpuDxe/CpuPageTable.c | 18 +++++++++++++++++-
> UefiCpuPkg/CpuDxe/CpuPageTable.h |  3 ++-
>  2 files changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c
> b/UefiCpuPkg/CpuDxe/CpuPageTable.c
> index 16a2528b55..36ce90d66c 100644
> --- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
> +++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
> @@ -184,6 +184,9 @@ GetCurrentPagingContext (
>      if (Cr4.Bits.PAE != 0) {
>        mPagingContext.ContextData.Ia32.Attributes |=
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE;
>      }
> +    if (Cr4.Bits.LA57 != 0) {
> +      mPagingContext.ContextData.Ia32.Attributes |=
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_5_LEVEL;
> +    }
> 
>      AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL);
>      if (RegEax >= CPUID_EXTENDED_CPU_SIG) { @@ -273,14 +276,17 @@
> GetPageTableEntry (
>    UINTN                 Index2;
>    UINTN                 Index3;
>    UINTN                 Index4;
> +  UINTN                 Index5;
>    UINT64                *L1PageTable;
>    UINT64                *L2PageTable;
>    UINT64                *L3PageTable;
>    UINT64                *L4PageTable;
> +  UINT64                *L5PageTable;
>    UINT64                AddressEncMask;
> 
>    ASSERT (PagingContext != NULL);
> 
> +  Index5 = ((UINTN)RShiftU64 (Address, 48)) & PAGING_PAE_INDEX_MASK;
>    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; @@ -
> 291,7 +297,17 @@ GetPageTableEntry (
>    AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask)
> & PAGING_1G_ADDRESS_MASK_64;
> 
>    if (PagingContext->MachineType == IMAGE_FILE_MACHINE_X64) {
> -    L4PageTable = (UINT64 *)(UINTN)PagingContext-
> >ContextData.X64.PageTableBase;
> +    if ((PagingContext->ContextData.X64.Attributes &
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_5_LEVEL) != 0)
> {
> +      L5PageTable = (UINT64 *)(UINTN)PagingContext-
> >ContextData.X64.PageTableBase;
> +      if (L5PageTable[Index5] == 0) {
> +        *PageAttribute = PageNone;
> +        return NULL;
> +      }
> +
> +      L4PageTable = (UINT64 *)(UINTN)(L5PageTable[Index5] &
> ~AddressEncMask & PAGING_4K_ADDRESS_MASK_64);
> +    } else {
> +      L4PageTable = (UINT64 *)(UINTN)PagingContext-
> >ContextData.X64.PageTableBase;
> +    }
>      if (L4PageTable[Index4] == 0) {
>        *PageAttribute = PageNone;
>        return NULL;
> diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.h
> b/UefiCpuPkg/CpuDxe/CpuPageTable.h
> index 02d62f2b14..f845956f73 100644
> --- a/UefiCpuPkg/CpuDxe/CpuPageTable.h
> +++ b/UefiCpuPkg/CpuDxe/CpuPageTable.h
> @@ -1,7 +1,7 @@
>  /** @file
>    Page table management header file.
> 
> -  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) 2017 - 2019, Intel Corporation. All rights
> + reserved.<BR>
>    SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -14,6 +14,7 @@
>  #define PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PSE
> BIT0
>  #define PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE
> BIT1
>  #define
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAGE_1G_SU
> PPORT  BIT2
> +#define
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_5_LEVEL
> BIT3
>  #define
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_WP_ENABLE
> BIT30
>  #define
> PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_XD_ACTIVATE
> D     BIT31
>  // Other bits are reserved for future use
> --
> 2.21.0.windows.1