Re: [edk2-devel] [PATCH v3 1/2] UefiCpuPkg: Remove FIT based microcode shadow logic from MpInitLib.

["Michael D Kinney" <michael.d.kinney@intel.com>]

Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>

Mike

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On
> Behalf Of Siyuan, Fu
> Sent: Wednesday, February 12, 2020 5:57 PM
> To: devel@edk2.groups.io
> Cc: Dong, Eric <eric.dong@intel.com>; Ni, Ray
> <ray.ni@intel.com>; Laszlo Ersek <lersek@redhat.com>
> Subject: [edk2-devel] [PATCH v3 1/2] UefiCpuPkg: Remove
> FIT based microcode shadow logic from MpInitLib.
> 
> V2 Changes:
> Rename EDKII_PEI_CPU_MICROCODE_ID to
> EDKII_PEI_MICROCODE_CPU_ID.
> Return EFI_UNSUPPORTED instead of EFI_NOT_FOUND if no
> platform
> microcode shadow PPI/Protocol is found.
> Remove PcdCpuShadowMicrocodeByFit related tokens from
> UefiCpuPkg.uni
> V3 Changes
> Add comments to DXE version PlatformShadowMicrocode().
> 
> Commit c7c964b and dd01704 add header file for FIT
> table and update
> MpInitLib to support FIT based microcode shadow
> operation. There are
> comments that FIT is Intel specific specification
> instead of industry
> standard, which should not be placed in EDK2 MdePkg and
> UefiCpuPkg.
> So this patch adds a platform PPI for the microcode
> shadow logic, and
> remove the FIT related code from EDK2.
> The FIT based microcode shadow support will be
> implemented as a new
> platform PEIM in IntelSiliconPkg in edk2-platforms.
> This patch doesn't provide a DXE version shadow
> microcode protocol,
> a platform which only uses DxeMpInitLib instance only
> supports PCD
> based microcode shadowing.
> 
> A detailed design doc can be found here:
> https://edk2.groups.io/g/devel/files/Designs/2020/0214/
> Support%20
> the%202nd%20Microcode%20FV%20Flash%20Region.pdf
> 
> TEST: Tested on FIT enabled platform.
> BZ:
> https://tianocore.acgmultimedia.com/show_bug.cgi?id=244
> 9
> 
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Signed-off-by: Siyuan Fu <siyuan.fu@intel.com>
> ---
>  UefiCpuPkg/Include/Ppi/ShadowMicrocode.h      |  66
> +++++++++++
>  UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf |   1 -
>  UefiCpuPkg/Library/MpInitLib/DxeMpLib.c       |  26
> ++++-
>  UefiCpuPkg/Library/MpInitLib/Microcode.c      | 105 +-
> ----------------
>  UefiCpuPkg/Library/MpInitLib/MpLib.h          |  19
> +++-
>  UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf |   4 +-
>  UefiCpuPkg/Library/MpInitLib/PeiMpLib.c       |  68
> ++++++++++++
>  UefiCpuPkg/UefiCpuPkg.dec                     |  11 +-
>  UefiCpuPkg/UefiCpuPkg.uni                     |   6 -
>  9 files changed, 183 insertions(+), 123 deletions(-)
>  create mode 100644
> UefiCpuPkg/Include/Ppi/ShadowMicrocode.h
> 
> diff --git a/UefiCpuPkg/Include/Ppi/ShadowMicrocode.h
> b/UefiCpuPkg/Include/Ppi/ShadowMicrocode.h
> new file mode 100644
> index 0000000000..be48965422
> --- /dev/null
> +++ b/UefiCpuPkg/Include/Ppi/ShadowMicrocode.h
> @@ -0,0 +1,66 @@
> +/** @file
> +  This file declares EDKII Shadow Microcode PPI.
> +
> +  Copyright (c) 2020, Intel Corporation. All rights
> reserved.<BR>
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef __PPI_SHADOW_MICROCODE_H__
> +#define __PPI_SHADOW_MICROCODE_H__
> +
> +#define EDKII_PEI_SHADOW_MICROCODE_PPI_GUID \
> +  { \
> +    0x430f6965, 0x9a69, 0x41c5, { 0x93, 0xed, 0x8b,
> 0xf0, 0x64, 0x35, 0xc1, 0xc6 } \
> +  }
> +
> +typedef struct _EDKII_PEI_SHADOW_MICROCODE_PPI
> EDKII_PEI_SHADOW_MICROCODE_PPI;
> +
> +typedef struct {
> +  UINT32         ProcessorSignature;
> +  UINT8          PlatformId;
> +} EDKII_PEI_MICROCODE_CPU_ID;
> +
> +/**
> +  Shadow microcode update patches to memory.
> +
> +  The function is used for shadowing microcode update
> patches to a continuous memory.
> +  It shall allocate memory buffer and only shadow the
> microcode patches for those
> +  processors specified by MicrocodeCpuId array. The
> checksum verification may be
> +  skiped in this function so the caller must perform
> checksum verification before
> +  using the microcode patches in returned memory
> buffer.
> +
> +  @param[in]  This                 The PPI instance
> pointer.
> +  @param[in]  CpuIdCount           Number of elements
> in MicrocodeCpuId array.
> +  @param[in]  MicrocodeCpuId       A pointer to an
> array of EDKII_PEI_MICROCODE_CPU_ID
> +                                   structures.
> +  @param[out] BufferSize           Pointer to receive
> the total size of Buffer.
> +  @param[out] Buffer               Pointer to receive
> address of allocated memory
> +                                   with microcode
> patches data in it.
> +
> +  @retval EFI_SUCCESS              The microcode has
> been shadowed to memory.
> +  @retval EFI_OUT_OF_RESOURCES     The operation fails
> due to lack of resources.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *EDKII_PEI_SHADOW_MICROCODE) (
> +  IN  EDKII_PEI_SHADOW_MICROCODE_PPI        *This,
> +  IN  UINTN
> CpuIdCount,
> +  IN  EDKII_PEI_MICROCODE_CPU_ID
> *MicrocodeCpuId,
> +  OUT UINTN
> *BufferSize,
> +  OUT VOID                                  **Buffer
> +  );
> +
> +///
> +/// This PPI is installed by some platform or chipset-
> specific PEIM that
> +/// abstracts handling microcode shadow support.
> +///
> +struct _EDKII_PEI_SHADOW_MICROCODE_PPI {
> +  EDKII_PEI_SHADOW_MICROCODE          ShadowMicrocode;
> +};
> +
> +extern EFI_GUID gEdkiiPeiShadowMicrocodePpiGuid;
> +
> +#endif
> +
> diff --git
> a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
> b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
> index 9e6cce0895..45aaa179ff 100644
> --- a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
> +++ b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
> @@ -69,6 +69,5 @@
> 
> gUefiCpuPkgTokenSpaceGuid.PcdCpuMicrocodePatchRegionSiz
> e         ## CONSUMES
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApLoopMode
> ## CONSUMES
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApTargetCstate
> ## SOMETIMES_CONSUMES
> -  gUefiCpuPkgTokenSpaceGuid.PcdCpuShadowMicrocodeByFit
> ## CONSUMES
>    gEfiMdeModulePkgTokenSpaceGuid.PcdCpuStackGuard
> ## CONSUMES
> 
> diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
> b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
> index b17e287bbf..dad5e22d22 100644
> --- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
> +++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
> @@ -1,7 +1,7 @@
>  /** @file
>    MP initialize support functions for DXE phase.
> 
> -  Copyright (c) 2016 - 2019, Intel Corporation. All
> rights reserved.<BR>
> +  Copyright (c) 2016 - 2020, Intel Corporation. All
> rights reserved.<BR>
>    SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -816,3 +816,27 @@ MpInitLibEnableDisableAP (
> 
>    return Status;
>  }
> +
> +/**
> +  This funtion will try to invoke platform specific
> microcode shadow logic to
> +  relocate microcode update patches into memory.
> +
> +  @param[in] CpuMpData  The pointer to CPU MP Data
> structure.
> +
> +  @retval EFI_SUCCESS              Shadow microcode
> success.
> +  @retval EFI_OUT_OF_RESOURCES     No enough resource
> to complete the operation.
> +  @retval EFI_UNSUPPORTED          Can't find platform
> specific microcode shadow
> +                                   PPI/Protocol.
> +**/
> +EFI_STATUS
> +PlatformShadowMicrocode (
> +  IN OUT CPU_MP_DATA             *CpuMpData
> +  )
> +{
> +  //
> +  // There is no DXE version of platform shadow
> microcode protocol so far.
> +  // A platform which only uses DxeMpInitLib instance
> could only supports
> +  // the PCD based microcode shadowing.
> +  //
> +  return EFI_UNSUPPORTED;
> +}
> diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c
> b/UefiCpuPkg/Library/MpInitLib/Microcode.c
> index 67e214d463..15629591e2 100644
> --- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
> +++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
> @@ -619,109 +619,6 @@ OnExit:
>    return;
>  }
> 
> -/**
> -  Shadow the required microcode patches data into
> memory according to FIT microcode entry.
> -
> -  @param[in, out]  CpuMpData    The pointer to CPU MP
> Data structure.
> -
> -  @return EFI_SUCCESS           Microcode patch is
> shadowed into memory.
> -  @return EFI_UNSUPPORTED       FIT based microcode
> shadowing is not supported.
> -  @return EFI_OUT_OF_RESOURCES  No enough memory
> resource.
> -  @return EFI_NOT_FOUND         There is something
> wrong in FIT microcode entry.
> -
> -**/
> -EFI_STATUS
> -ShadowMicrocodePatchByFit (
> -  IN OUT CPU_MP_DATA             *CpuMpData
> -  )
> -{
> -  UINT64                            FitPointer;
> -  FIRMWARE_INTERFACE_TABLE_ENTRY    *FitEntry;
> -  UINT32                            EntryNum;
> -  UINT32                            Index;
> -  MICROCODE_PATCH_INFO              *PatchInfoBuffer;
> -  UINTN                             MaxPatchNumber;
> -  CPU_MICROCODE_HEADER
> *MicrocodeEntryPoint;
> -  UINTN                             PatchCount;
> -  UINTN                             TotalSize;
> -  UINTN                             TotalLoadSize;
> -
> -  if (!FeaturePcdGet (PcdCpuShadowMicrocodeByFit)) {
> -    return EFI_UNSUPPORTED;
> -  }
> -
> -  FitPointer = *(UINT64 *) (UINTN)
> FIT_POINTER_ADDRESS;
> -  if ((FitPointer == 0) ||
> -      (FitPointer == 0xFFFFFFFFFFFFFFFF) ||
> -      (FitPointer == 0xEEEEEEEEEEEEEEEE)) {
> -    //
> -    // No FIT table.
> -    //
> -    ASSERT (FALSE);
> -    return EFI_NOT_FOUND;
> -  }
> -  FitEntry = (FIRMWARE_INTERFACE_TABLE_ENTRY *)
> (UINTN) FitPointer;
> -  if ((FitEntry[0].Type != FIT_TYPE_00_HEADER) ||
> -      (FitEntry[0].Address != FIT_TYPE_00_SIGNATURE))
> {
> -    //
> -    // Invalid FIT table, treat it as no FIT table.
> -    //
> -    ASSERT (FALSE);
> -    return EFI_NOT_FOUND;
> -  }
> -
> -  EntryNum = *(UINT32 *)(&FitEntry[0].Size[0]) &
> 0xFFFFFF;
> -
> -  //
> -  // Calculate microcode entry number
> -  //
> -  MaxPatchNumber = 0;
> -  for (Index = 0; Index < EntryNum; Index++) {
> -    if (FitEntry[Index].Type == FIT_TYPE_01_MICROCODE)
> {
> -      MaxPatchNumber++;
> -    }
> -  }
> -  if (MaxPatchNumber == 0) {
> -    return EFI_NOT_FOUND;
> -  }
> -
> -  PatchInfoBuffer = AllocatePool (MaxPatchNumber *
> sizeof (MICROCODE_PATCH_INFO));
> -  if (PatchInfoBuffer == NULL) {
> -    return EFI_OUT_OF_RESOURCES;
> -  }
> -
> -  //
> -  // Fill up microcode patch info buffer according to
> FIT table.
> -  //
> -  PatchCount = 0;
> -  TotalLoadSize = 0;
> -  for (Index = 0; Index < EntryNum; Index++) {
> -    if (FitEntry[Index].Type == FIT_TYPE_01_MICROCODE)
> {
> -      MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *)
> (UINTN) FitEntry[Index].Address;
> -      TotalSize = (MicrocodeEntryPoint->DataSize == 0)
> ? 2048 : MicrocodeEntryPoint->TotalSize;
> -      if (IsMicrocodePatchNeedLoad (CpuMpData,
> MicrocodeEntryPoint)) {
> -        PatchInfoBuffer[PatchCount].Address     =
> (UINTN) MicrocodeEntryPoint;
> -        PatchInfoBuffer[PatchCount].Size        =
> TotalSize;
> -        TotalLoadSize += TotalSize;
> -        PatchCount++;
> -      }
> -    }
> -  }
> -
> -  if (PatchCount != 0) {
> -    DEBUG ((
> -      DEBUG_INFO,
> -      "%a: 0x%x microcode patches will be loaded into
> memory, with size 0x%x.\n",
> -      __FUNCTION__, PatchCount, TotalLoadSize
> -      ));
> -
> -    ShadowMicrocodePatchWorker (CpuMpData,
> PatchInfoBuffer, PatchCount, TotalLoadSize);
> -  }
> -
> -  FreePool (PatchInfoBuffer);
> -  return EFI_SUCCESS;
> -}
> -
>  /**
>    Shadow the required microcode patches data into
> memory.
> 
> @@ -734,7 +631,7 @@ ShadowMicrocodeUpdatePatch (
>  {
>    EFI_STATUS     Status;
> 
> -  Status = ShadowMicrocodePatchByFit (CpuMpData);
> +  Status = PlatformShadowMicrocode (CpuMpData);
>    if (EFI_ERROR (Status)) {
>      ShadowMicrocodePatchByPcd (CpuMpData);
>    }
> diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h
> b/UefiCpuPkg/Library/MpInitLib/MpLib.h
> index a6eab5f3d7..455cb3f09a 100644
> --- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
> +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
> @@ -31,9 +31,6 @@
> 
>  #include <Guid/MicrocodePatchHob.h>
> 
> -#include <IndustryStandard/FirmwareInterfaceTable.h>
> -
> -
>  #define WAKEUP_AP_SIGNAL SIGNATURE_32 ('S', 'T', 'A',
> 'P')
> 
>  #define CPU_INIT_MP_LIB_HOB_GUID \
> @@ -657,5 +654,21 @@ GetProcessorNumber (
>    OUT UINTN                    *ProcessorNumber
>    );
> 
> +/**
> +  This funtion will try to invoke platform specific
> microcode shadow logic to
> +  relocate microcode update patches into memory.
> +
> +  @param[in] CpuMpData  The pointer to CPU MP Data
> structure.
> +
> +  @retval EFI_SUCCESS              Shadow microcode
> success.
> +  @retval EFI_OUT_OF_RESOURCES     No enough resource
> to complete the operation.
> +  @retval EFI_UNSUPPORTED          Can't find platform
> specific microcode shadow
> +                                   PPI/Protocol.
> +**/
> +EFI_STATUS
> +PlatformShadowMicrocode (
> +  IN OUT CPU_MP_DATA             *CpuMpData
> +  );
> +
>  #endif
> 
> diff --git
> a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> index 555125a7c5..d78d328b42 100644
> --- a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> +++ b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
> @@ -60,7 +60,9 @@
> 
> gUefiCpuPkgTokenSpaceGuid.PcdCpuMicrocodePatchRegionSiz
> e         ## CONSUMES
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApLoopMode
> ## CONSUMES
>    gUefiCpuPkgTokenSpaceGuid.PcdCpuApTargetCstate
> ## SOMETIMES_CONSUMES
> -  gUefiCpuPkgTokenSpaceGuid.PcdCpuShadowMicrocodeByFit
> ## CONSUMES
> +
> +[Ppis]
> +  gEdkiiPeiShadowMicrocodePpiGuid        ##
> SOMETIMES_CONSUMES
> 
>  [Guids]
>    gEdkiiS3SmmInitDoneGuid
> diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> index 6ecbed39ec..17b60903c5 100644
> --- a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> +++ b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
> @@ -9,6 +9,7 @@
>  #include "MpLib.h"
>  #include <Library/PeiServicesLib.h>
>  #include <Guid/S3SmmInitDone.h>
> +#include <Ppi/ShadowMicrocode.h>
> 
>  /**
>    S3 SMM Init Done notification function.
> @@ -639,4 +640,71 @@ MpInitLibEnableDisableAP (
>    return EnableDisableApWorker (ProcessorNumber,
> EnableAP, HealthFlag);
>  }
> 
> +/**
> +  This funtion will try to invoke platform specific
> microcode shadow logic to
> +  relocate microcode update patches into memory.
> +
> +  @param[in] CpuMpData  The pointer to CPU MP Data
> structure.
> 
> +  @retval EFI_SUCCESS              Shadow microcode
> success.
> +  @retval EFI_OUT_OF_RESOURCES     No enough resource
> to complete the operation.
> +  @retval EFI_UNSUPPORTED          Can't find platform
> specific microcode shadow
> +                                   PPI/Protocol.
> +**/
> +EFI_STATUS
> +PlatformShadowMicrocode (
> +  IN OUT CPU_MP_DATA             *CpuMpData
> +  )
> +{
> +  EFI_STATUS                         Status;
> +  EDKII_PEI_SHADOW_MICROCODE_PPI
> *ShadowMicrocodePpi;
> +  UINTN                              CpuCount;
> +  EDKII_PEI_MICROCODE_CPU_ID         *MicrocodeCpuId;
> +  UINTN                              Index;
> +  UINTN                              BufferSize;
> +  VOID                               *Buffer;
> +
> +  Status = PeiServicesLocatePpi (
> +             &gEdkiiPeiShadowMicrocodePpiGuid,
> +             0,
> +             NULL,
> +             (VOID **) &ShadowMicrocodePpi
> +             );
> +  if (EFI_ERROR (Status)) {
> +    return EFI_UNSUPPORTED;
> +  }
> +
> +  CpuCount = CpuMpData->CpuCount;
> +  MicrocodeCpuId = (EDKII_PEI_MICROCODE_CPU_ID *)
> AllocateZeroPool (sizeof (EDKII_PEI_MICROCODE_CPU_ID) *
> CpuCount);
> +  if (MicrocodeCpuId == NULL) {
> +    return EFI_OUT_OF_RESOURCES;
> +  }
> +
> +  for (Index = 0; Index < CpuMpData->CpuCount;
> Index++) {
> +    MicrocodeCpuId[Index].ProcessorSignature =
> CpuMpData->CpuData[Index].ProcessorSignature;
> +    MicrocodeCpuId[Index].PlatformId         =
> CpuMpData->CpuData[Index].PlatformId;
> +  }
> +
> +  Status = ShadowMicrocodePpi->ShadowMicrocode (
> +             ShadowMicrocodePpi,
> +             CpuCount,
> +             MicrocodeCpuId,
> +             &BufferSize,
> +             &Buffer
> +             );
> +  FreePool (MicrocodeCpuId);
> +  if (EFI_ERROR (Status)) {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  CpuMpData->MicrocodePatchAddress    = (UINTN)
> Buffer;
> +  CpuMpData->MicrocodePatchRegionSize = BufferSize;
> +
> +  DEBUG ((
> +    DEBUG_INFO,
> +    "%a: Required microcode patches have been loaded
> at 0x%lx, with size 0x%lx.\n",
> +    __FUNCTION__, CpuMpData->MicrocodePatchAddress,
> CpuMpData->MicrocodePatchRegionSize
> +    ));
> +
> +  return EFI_SUCCESS;
> +}
> diff --git a/UefiCpuPkg/UefiCpuPkg.dec
> b/UefiCpuPkg/UefiCpuPkg.dec
> index a6ebdde1cf..e91dc68cbe 100644
> --- a/UefiCpuPkg/UefiCpuPkg.dec
> +++ b/UefiCpuPkg/UefiCpuPkg.dec
> @@ -1,7 +1,7 @@
>  ## @file  UefiCpuPkg.dec
>  # This Package provides UEFI compatible CPU modules
> and libraries.
>  #
> -# Copyright (c) 2007 - 2019, Intel Corporation. All
> rights reserved.<BR>
> +# Copyright (c) 2007 - 2020, Intel Corporation. All
> rights reserved.<BR>
>  #
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
> @@ -81,6 +81,9 @@
>  [Ppis]
>    gEdkiiPeiMpServices2PpiGuid =    { 0x5cb9cb3d,
> 0x31a4, 0x480c, { 0x94, 0x98, 0x29, 0xd2, 0x69, 0xba,
> 0xcf, 0xba}}
> 
> +  ## Include/Ppi/ShadowMicrocode.h
> +  gEdkiiPeiShadowMicrocodePpiGuid = { 0x430f6965,
> 0x9a69, 0x41c5, { 0x93, 0xed, 0x8b, 0xf0, 0x64, 0x35,
> 0xc1, 0xc6 }}
> +
>  [PcdsFeatureFlag]
>    ## Indicates if SMM Profile will be enabled.
>    #  If enabled, instruction executions in and data
> accesses to memory outside of SMRAM will be logged.
> @@ -139,12 +142,6 @@
>    # @Prompt Lock SMM Feature Control MSR.
> 
> gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmFeatureControlMsrLoc
> k|TRUE|BOOLEAN|0x3213210B
> 
> -  ## Indicates if FIT based microcode shadowing will
> be enabled.<BR><BR>
> -  #   TRUE  - FIT base microcode shadowing will be
> enabled.<BR>
> -  #   FALSE - FIT base microcode shadowing will be
> disabled.<BR>
> -  # @Prompt FIT based microcode shadowing.
> -
> gUefiCpuPkgTokenSpaceGuid.PcdCpuShadowMicrocodeByFit|FA
> LSE|BOOLEAN|0x3213210D
> -
>  [PcdsFixedAtBuild]
>    ## List of exception vectors which need switching
> stack.
>    #  This PCD will only take into effect if
> PcdCpuStackGuard is enabled.
> diff --git a/UefiCpuPkg/UefiCpuPkg.uni
> b/UefiCpuPkg/UefiCpuPkg.uni
> index 2db49e841b..c0d6ed5136 100644
> --- a/UefiCpuPkg/UefiCpuPkg.uni
> +++ b/UefiCpuPkg/UefiCpuPkg.uni
> @@ -100,12 +100,6 @@
> 
> "TRUE  - locked.<BR>\n"
> 
> "FALSE - unlocked.<BR>"
> 
> -#string
> STR_gUefiCpuPkgTokenSpaceGuid_PcdCpuShadowMicrocodeByFi
> t_PROMPT  #language en-US "FIT based microcode
> shadowing"
> -
> -#string
> STR_gUefiCpuPkgTokenSpaceGuid_PcdCpuShadowMicrocodeByFi
> t_HELP  #language en-US "Indicates if FIT based
> microcode shadowing will be enabled.<BR><BR>\n"
> -
> "TRUE  - FIT base microcode shadowing will be
> enabled.<BR>\n"
> -
> "FALSE - FIT base microcode shadowing will be
> disabled.<BR>"
> -
>  #string
> STR_gUefiCpuPkgTokenSpaceGuid_PcdPeiTemporaryRamStackSi
> ze_PROMPT  #language en-US "Stack size in the temporary
> RAM"
> 
>  #string
> STR_gUefiCpuPkgTokenSpaceGuid_PcdPeiTemporaryRamStackSi
> ze_HELP  #language en-US "Specifies stack size in the
> temporary RAM. 0 means half of TemporaryRamSize."
> --
> 2.19.1.windows.1
> 
> 
>