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From: "Yao, Jiewen" <jiewen.yao@intel.com>
To: "Xu, Min M" <min.m.xu@intel.com>,
	"devel@edk2.groups.io" <devel@edk2.groups.io>
Cc: "Dong, Eric" <eric.dong@intel.com>, "Ni, Ray" <ray.ni@intel.com>,
	"Kinney, Michael D" <michael.d.kinney@intel.com>,
	"Huang, Yanbo" <yanbo.huang@intel.com>
Subject: Re: [PATCH V1 1/1] UefiCpuPkg: Add back VmgExitLib to fix downstream incompatibility issue
Date: Tue, 22 Nov 2022 14:18:13 +0000	[thread overview]
Message-ID: <MW4PR11MB587256B13BDC781B7C4C8EE58C0D9@MW4PR11MB5872.namprd11.prod.outlook.com> (raw)
In-Reply-To: <20221122141637.1631-1-min.m.xu@intel.com>

Can we put this patch to downstream directly? Why it must be upstream?


> -----Original Message-----
> From: Xu, Min M <min.m.xu@intel.com>
> Sent: Tuesday, November 22, 2022 10:17 PM
> To: devel@edk2.groups.io
> Cc: Xu, Min M <min.m.xu@intel.com>; Dong, Eric <eric.dong@intel.com>;
> Ni, Ray <ray.ni@intel.com>; Kinney, Michael D
> <michael.d.kinney@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Huang, Yanbo <yanbo.huang@intel.com>
> Subject: [PATCH V1 1/1] UefiCpuPkg: Add back VmgExitLib to fix
> downstream incompatibility issue
> 
> From: Min M Xu <min.m.xu@intel.com>
> 
> VmgExitLib is renamed as CcExitLib in commit a89f558d3c. This brought
> incompatibility issues for platforms downstream. This patch adds back
> VmgExitLib (VmgExitLib.h & VmgExitLibNull) to fix the issue this time
> and we will work out the long term solution later. After the
> incompatibility of downstream is resolved, this patch will be reverted.
> 
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Huang Yanbo <yanbo.huang@intel.com>
> Signed-off-by: Min Xu <min.m.xu@intel.com>
> ---
>  UefiCpuPkg/Include/Library/VmgExitLib.h       | 173 ++++++++++++++++++
>  .../Library/VmgExitLibNull/VmTdExitNull.c     |  38 ++++
>  .../Library/VmgExitLibNull/VmgExitLibNull.c   | 165 +++++++++++++++++
>  .../Library/VmgExitLibNull/VmgExitLibNull.inf |  28 +++
>  .../Library/VmgExitLibNull/VmgExitLibNull.uni |  15 ++
>  UefiCpuPkg/UefiCpuPkg.dec                     |   3 +
>  UefiCpuPkg/UefiCpuPkg.dsc                     |   2 +
>  7 files changed, 424 insertions(+)
>  create mode 100644 UefiCpuPkg/Include/Library/VmgExitLib.h
>  create mode 100644 UefiCpuPkg/Library/VmgExitLibNull/VmTdExitNull.c
>  create mode 100644 UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c
>  create mode 100644
> UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
>  create mode 100644
> UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.uni
> 
> diff --git a/UefiCpuPkg/Include/Library/VmgExitLib.h
> b/UefiCpuPkg/Include/Library/VmgExitLib.h
> new file mode 100644
> index 000000000000..9fab90afd226
> --- /dev/null
> +++ b/UefiCpuPkg/Include/Library/VmgExitLib.h
> @@ -0,0 +1,173 @@
> +/** @file
> +  Public header file for the VMGEXIT Support library class.
> +
> +  This library class defines some routines used when invoking the VMGEXIT
> +  instruction in support of SEV-ES and to handle #VC exceptions.
> +
> +  Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef VMG_EXIT_LIB_H_
> +#define VMG_EXIT_LIB_H_
> +
> +#include <Protocol/DebugSupport.h>
> +#include <Register/Amd/Ghcb.h>
> +
> +#define VE_EXCEPTION  20
> +
> +/**
> +  Perform VMGEXIT.
> +
> +  Sets the necessary fields of the GHCB, invokes the VMGEXIT instruction
> and
> +  then handles the return actions.
> +
> +  @param[in, out]  Ghcb       A pointer to the GHCB
> +  @param[in]       ExitCode   VMGEXIT code to be assigned to the
> SwExitCode
> +                              field of the GHCB.
> +  @param[in]       ExitInfo1  VMGEXIT information to be assigned to the
> +                              SwExitInfo1 field of the GHCB.
> +  @param[in]       ExitInfo2  VMGEXIT information to be assigned to the
> +                              SwExitInfo2 field of the GHCB.
> +
> +  @retval  0                  VMGEXIT succeeded.
> +  @return                     Exception number to be propagated, VMGEXIT
> +                              processing did not succeed.
> +
> +**/
> +UINT64
> +EFIAPI
> +VmgExit (
> +  IN OUT GHCB    *Ghcb,
> +  IN     UINT64  ExitCode,
> +  IN     UINT64  ExitInfo1,
> +  IN     UINT64  ExitInfo2
> +  );
> +
> +/**
> +  Perform pre-VMGEXIT initialization/preparation.
> +
> +  Performs the necessary steps in preparation for invoking VMGEXIT. Must
> be
> +  called before setting any fields within the GHCB.
> +
> +  @param[in, out]  Ghcb            A pointer to the GHCB
> +  @param[in, out]  InterruptState  A pointer to hold the current interrupt
> +                                   state, used for restoring in VmgDone ()
> +
> +**/
> +VOID
> +EFIAPI
> +VmgInit (
> +  IN OUT GHCB     *Ghcb,
> +  IN OUT BOOLEAN  *InterruptState
> +  );
> +
> +/**
> +  Perform post-VMGEXIT cleanup.
> +
> +  Performs the necessary steps to cleanup after invoking VMGEXIT. Must
> be
> +  called after obtaining needed fields within the GHCB.
> +
> +  @param[in, out]  Ghcb            A pointer to the GHCB
> +  @param[in]       InterruptState  An indicator to conditionally (re)enable
> +                                   interrupts
> +
> +**/
> +VOID
> +EFIAPI
> +VmgDone (
> +  IN OUT GHCB     *Ghcb,
> +  IN     BOOLEAN  InterruptState
> +  );
> +
> +/**
> +  Marks a specified offset as valid in the GHCB.
> +
> +  The ValidBitmap area represents the areas of the GHCB that have been
> marked
> +  valid. Set the bit in ValidBitmap for the input offset.
> +
> +  @param[in, out]  Ghcb       A pointer to the GHCB
> +  @param[in]       Offset     Qword offset in the GHCB to mark valid
> +
> +**/
> +VOID
> +EFIAPI
> +VmgSetOffsetValid (
> +  IN OUT GHCB           *Ghcb,
> +  IN     GHCB_REGISTER  Offset
> +  );
> +
> +/**
> +  Checks if a specified offset is valid in the GHCB.
> +
> +  The ValidBitmap area represents the areas of the GHCB that have been
> marked
> +  valid. Return whether the bit in the ValidBitmap is set for the input offset.
> +
> +  @param[in]  Ghcb            A pointer to the GHCB
> +  @param[in]  Offset          Qword offset in the GHCB to mark valid
> +
> +  @retval TRUE                Offset is marked valid in the GHCB
> +  @retval FALSE               Offset is not marked valid in the GHCB
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +VmgIsOffsetValid (
> +  IN GHCB           *Ghcb,
> +  IN GHCB_REGISTER  Offset
> +  );
> +
> +/**
> +  Handle a #VC exception.
> +
> +  Performs the necessary processing to handle a #VC exception.
> +
> +  The base library function returns an error equal to VC_EXCEPTION,
> +  to be propagated to the standard exception handling stack.
> +
> +  @param[in, out]  ExceptionType  Pointer to an EFI_EXCEPTION_TYPE to
> be set
> +                                  as value to use on error.
> +  @param[in, out]  SystemContext  Pointer to EFI_SYSTEM_CONTEXT
> +
> +  @retval  EFI_SUCCESS            Exception handled
> +  @retval  EFI_UNSUPPORTED        #VC not supported, (new) exception
> value to
> +                                  propagate provided
> +  @retval  EFI_PROTOCOL_ERROR     #VC handling failed, (new) exception
> value to
> +                                  propagate provided
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VmgExitHandleVc (
> +  IN OUT EFI_EXCEPTION_TYPE  *ExceptionType,
> +  IN OUT EFI_SYSTEM_CONTEXT  SystemContext
> +  );
> +
> +/**
> +  Handle a #VE exception.
> +
> +  Performs the necessary processing to handle a #VE exception.
> +
> +  The base library function returns an error equal to VE_EXCEPTION,
> +  to be propagated to the standard exception handling stack.
> +
> +  @param[in, out]  ExceptionType  Pointer to an EFI_EXCEPTION_TYPE to
> be set
> +                                  as value to use on error.
> +  @param[in, out]  SystemContext  Pointer to EFI_SYSTEM_CONTEXT
> +
> +  @retval  EFI_SUCCESS            Exception handled
> +  @retval  EFI_UNSUPPORTED        #VE not supported, (new) exception
> value to
> +                                  propagate provided
> +  @retval  EFI_PROTOCOL_ERROR     #VE handling failed, (new) exception
> value to
> +                                  propagate provided
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VmTdExitHandleVe (
> +  IN OUT EFI_EXCEPTION_TYPE  *ExceptionType,
> +  IN OUT EFI_SYSTEM_CONTEXT  SystemContext
> +  );
> +
> +#endif
> diff --git a/UefiCpuPkg/Library/VmgExitLibNull/VmTdExitNull.c
> b/UefiCpuPkg/Library/VmgExitLibNull/VmTdExitNull.c
> new file mode 100644
> index 000000000000..6a4e8087cb89
> --- /dev/null
> +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmTdExitNull.c
> @@ -0,0 +1,38 @@
> +/** @file
> +
> +  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
> +
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +#include <Base.h>
> +#include <Uefi.h>
> +#include <Library/VmgExitLib.h>
> +
> +/**
> +  Handle a #VE exception.
> +
> +  Performs the necessary processing to handle a #VE exception.
> +
> +  @param[in, out]  ExceptionType  Pointer to an EFI_EXCEPTION_TYPE to
> be set
> +                                  as value to use on error.
> +  @param[in, out]  SystemContext  Pointer to EFI_SYSTEM_CONTEXT
> +
> +  @retval  EFI_SUCCESS            Exception handled
> +  @retval  EFI_UNSUPPORTED        #VE not supported, (new) exception
> value to
> +                                  propagate provided
> +  @retval  EFI_PROTOCOL_ERROR     #VE handling failed, (new) exception
> value to
> +                                  propagate provided
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VmTdExitHandleVe (
> +  IN OUT EFI_EXCEPTION_TYPE  *ExceptionType,
> +  IN OUT EFI_SYSTEM_CONTEXT  SystemContext
> +  )
> +{
> +  *ExceptionType = VE_EXCEPTION;
> +
> +  return EFI_UNSUPPORTED;
> +}
> diff --git a/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c
> b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c
> new file mode 100644
> index 000000000000..d661d8597434
> --- /dev/null
> +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c
> @@ -0,0 +1,165 @@
> +/** @file
> +  VMGEXIT Base Support Library.
> +
> +  Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <Base.h>
> +#include <Uefi.h>
> +#include <Library/VmgExitLib.h>
> +
> +/**
> +  Perform VMGEXIT.
> +
> +  Sets the necessary fields of the GHCB, invokes the VMGEXIT instruction
> and
> +  then handles the return actions.
> +
> +  The base library function returns an error in the form of a
> +  GHCB_EVENT_INJECTION representing a GP_EXCEPTION.
> +
> +  @param[in, out]  Ghcb       A pointer to the GHCB
> +  @param[in]       ExitCode   VMGEXIT code to be assigned to the
> SwExitCode
> +                              field of the GHCB.
> +  @param[in]       ExitInfo1  VMGEXIT information to be assigned to the
> +                              SwExitInfo1 field of the GHCB.
> +  @param[in]       ExitInfo2  VMGEXIT information to be assigned to the
> +                              SwExitInfo2 field of the GHCB.
> +
> +  @retval  0                  VMGEXIT succeeded.
> +  @return                     Exception number to be propagated, VMGEXIT
> +                              processing did not succeed.
> +
> +**/
> +UINT64
> +EFIAPI
> +VmgExit (
> +  IN OUT GHCB    *Ghcb,
> +  IN     UINT64  ExitCode,
> +  IN     UINT64  ExitInfo1,
> +  IN     UINT64  ExitInfo2
> +  )
> +{
> +  GHCB_EVENT_INJECTION  Event;
> +
> +  Event.Uint64          = 0;
> +  Event.Elements.Vector = GP_EXCEPTION;
> +  Event.Elements.Type   = GHCB_EVENT_INJECTION_TYPE_EXCEPTION;
> +  Event.Elements.Valid  = 1;
> +
> +  return Event.Uint64;
> +}
> +
> +/**
> +  Perform pre-VMGEXIT initialization/preparation.
> +
> +  Performs the necessary steps in preparation for invoking VMGEXIT. Must
> be
> +  called before setting any fields within the GHCB.
> +
> +  @param[in, out]  Ghcb            A pointer to the GHCB
> +  @param[in, out]  InterruptState  A pointer to hold the current interrupt
> +                                   state, used for restoring in VmgDone ()
> +
> +**/
> +VOID
> +EFIAPI
> +VmgInit (
> +  IN OUT GHCB     *Ghcb,
> +  IN OUT BOOLEAN  *InterruptState
> +  )
> +{
> +}
> +
> +/**
> +  Perform post-VMGEXIT cleanup.
> +
> +  Performs the necessary steps to cleanup after invoking VMGEXIT. Must
> be
> +  called after obtaining needed fields within the GHCB.
> +
> +  @param[in, out]  Ghcb            A pointer to the GHCB
> +  @param[in]       InterruptState  An indicator to conditionally (re)enable
> +                                   interrupts
> +
> +**/
> +VOID
> +EFIAPI
> +VmgDone (
> +  IN OUT GHCB     *Ghcb,
> +  IN     BOOLEAN  InterruptState
> +  )
> +{
> +}
> +
> +/**
> +  Marks a field at the specified offset as valid in the GHCB.
> +
> +  The ValidBitmap area represents the areas of the GHCB that have been
> marked
> +  valid. Set the bit in ValidBitmap for the input offset.
> +
> +  @param[in, out] Ghcb    Pointer to the Guest-Hypervisor Communication
> Block
> +  @param[in]      Offset  Qword offset in the GHCB to mark valid
> +
> +**/
> +VOID
> +EFIAPI
> +VmgSetOffsetValid (
> +  IN OUT GHCB           *Ghcb,
> +  IN     GHCB_REGISTER  Offset
> +  )
> +{
> +}
> +
> +/**
> +  Checks if a specified offset is valid in the GHCB.
> +
> +  The ValidBitmap area represents the areas of the GHCB that have been
> marked
> +  valid. Return whether the bit in the ValidBitmap is set for the input offset.
> +
> +  @param[in]  Ghcb            A pointer to the GHCB
> +  @param[in]  Offset          Qword offset in the GHCB to mark valid
> +
> +  @retval TRUE                Offset is marked valid in the GHCB
> +  @retval FALSE               Offset is not marked valid in the GHCB
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +VmgIsOffsetValid (
> +  IN GHCB           *Ghcb,
> +  IN GHCB_REGISTER  Offset
> +  )
> +{
> +  return FALSE;
> +}
> +
> +/**
> +  Handle a #VC exception.
> +
> +  Performs the necessary processing to handle a #VC exception.
> +
> +  The base library function returns an error equal to VC_EXCEPTION,
> +  to be propagated to the standard exception handling stack.
> +
> +  @param[in, out]  ExceptionType  Pointer to an EFI_EXCEPTION_TYPE to
> be set
> +                                  as value to use on error.
> +  @param[in, out]  SystemContext  Pointer to EFI_SYSTEM_CONTEXT
> +
> +  @retval  EFI_SUCCESS            Exception handled
> +  @retval  EFI_UNSUPPORTED        #VC not supported, (new) exception
> value to
> +                                  propagate provided
> +  @retval  EFI_PROTOCOL_ERROR     #VC handling failed, (new) exception
> value to
> +                                  propagate provided
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VmgExitHandleVc (
> +  IN OUT EFI_EXCEPTION_TYPE  *ExceptionType,
> +  IN OUT EFI_SYSTEM_CONTEXT  SystemContext
> +  )
> +{
> +  *ExceptionType = VC_EXCEPTION;
> +
> +  return EFI_UNSUPPORTED;
> +}
> diff --git a/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
> b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
> new file mode 100644
> index 000000000000..06d3b0e7e63e
> --- /dev/null
> +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
> @@ -0,0 +1,28 @@
> +## @file
> +#  VMGEXIT Support Library.
> +#
> +#  Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
> +#  SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION                    = 0x00010005
> +  BASE_NAME                      = VmgExitLibNull
> +  MODULE_UNI_FILE                = VmgExitLibNull.uni
> +  FILE_GUID                      = cbd1992f-c26e-42f9-94d9-57d0468c4c56
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = VmgExitLib
> +
> +[Sources.common]
> +  VmgExitLibNull.c
> +  VmTdExitNull.c
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  UefiCpuPkg/UefiCpuPkg.dec
> +
> +[LibraryClasses]
> +  BaseLib
> +
> diff --git a/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.uni
> b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.uni
> new file mode 100644
> index 000000000000..8639bc0e8ce9
> --- /dev/null
> +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.uni
> @@ -0,0 +1,15 @@
> +// /** @file
> +// VMGEXIT support library instance.
> +//
> +// VMGEXIT support library instance.
> +//
> +// Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
> +// SPDX-License-Identifier: BSD-2-Clause-Patent
> +//
> +// **/
> +
> +
> +#string STR_MODULE_ABSTRACT             #language en-US "VMGEXIT
> support NULL library instance"
> +
> +#string STR_MODULE_DESCRIPTION          #language en-US "VMGEXIT
> support NULL library instance."
> +
> diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec
> index cff239d5283e..8058b679412f 100644
> --- a/UefiCpuPkg/UefiCpuPkg.dec
> +++ b/UefiCpuPkg/UefiCpuPkg.dec
> @@ -53,6 +53,9 @@
>    ##
>    MpInitLib|Include/Library/MpInitLib.h
> 
> +  ##  @libraryclass  Provides function to support VMGEXIT processing.
> +  VmgExitLib|Include/Library/VmgExitLib.h
> +
>    ##  @libraryclass  Provides function to support CcExit processing.
>    CcExitLib|Include/Library/CcExitLib.h
> 
> diff --git a/UefiCpuPkg/UefiCpuPkg.dsc b/UefiCpuPkg/UefiCpuPkg.dsc
> index 67b0ce46e455..57c74ba844d2 100644
> --- a/UefiCpuPkg/UefiCpuPkg.dsc
> +++ b/UefiCpuPkg/UefiCpuPkg.dsc
> @@ -59,6 +59,7 @@
> 
> PeCoffGetEntryPointLib|MdePkg/Library/BasePeCoffGetEntryPointLib/Base
> PeCoffGetEntryPointLib.inf
> 
> PeCoffExtraActionLib|MdePkg/Library/BasePeCoffExtraActionLibNull/BaseP
> eCoffExtraActionLibNull.inf
> 
> TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/T
> pmMeasurementLibNull.inf
> +  VmgExitLib|UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
>    CcExitLib|UefiCpuPkg/Library/CcExitLibNull/CcExitLibNull.inf
>    MicrocodeLib|UefiCpuPkg/Library/MicrocodeLib/MicrocodeLib.inf
> 
> SmmCpuRendezvousLib|UefiCpuPkg/Library/SmmCpuRendezvousLib/Smm
> CpuRendezvousLib.inf
> @@ -163,6 +164,7 @@
>    UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
>    UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf
> 
> UefiCpuPkg/Library/SmmCpuFeaturesLib/StandaloneMmCpuFeaturesLib.inf
> +  UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf
>    UefiCpuPkg/Library/CcExitLibNull/CcExitLibNull.inf
>    UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationPei.inf
>    UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationSmm.inf
> --
> 2.29.2.windows.2


      reply	other threads:[~2022-11-22 14:18 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-22 14:16 [PATCH V1 1/1] UefiCpuPkg: Add back VmgExitLib to fix downstream incompatibility issue Min Xu
2022-11-22 14:18 ` Yao, Jiewen [this message]

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