From 8714978781ad8f20dae18d6ca656bda7fc40735f Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Wed, 12 Aug 2020 15:21:36 -0500 Subject: [PATCH] UefiCpuPkg: Implement library support for VMGEXIT BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 To support handling #VC exceptions and issuing VMGEXIT instructions, create a library with functions that can be used to perform these #VC/VMGEXIT related operations. This includes functions for: - Handling #VC exceptions - Preparing for and issuing a VMGEXIT - Performing MMIO-related write operations to support flash emulation - Performing AP related boot opeations The base functions in this driver will not do anything and will return an error if a return value is required. It is expected that other packages (like OvmfPkg) will create a version of the library to fully support an SEV-ES guest. Cc: Eric Dong Cc: Ray Ni Cc: Laszlo Ersek Reviewed-by: Eric Dong Signed-off-by: Tom Lendacky Regression-tested-by: Laszlo Ersek --- UefiCpuPkg/Include/Library/VmgExitLib.h | 103 +++++++++++++++ .../Library/VmgExitLibNull/VmgExitLibNull.c | 121 ++++++++++++++++++ .../Library/VmgExitLibNull/VmgExitLibNull.inf | 27 ++++ .../Library/VmgExitLibNull/VmgExitLibNull.uni | 15 +++ UefiCpuPkg/UefiCpuPkg.dec | 3 + UefiCpuPkg/UefiCpuPkg.dsc | 2 + 6 files changed, 271 insertions(+) create mode 100644 UefiCpuPkg/Include/Library/VmgExitLib.h 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 0000000000..45fc27d35e --- /dev/null +++ b/UefiCpuPkg/Include/Library/VmgExitLib.h @@ -0,0 +1,103 @@ +/** @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.
+ SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#ifndef __VMG_EXIT_LIB_H__ +#define __VMG_EXIT_LIB_H__ + +#include +#include + + +/** + 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 + +**/ +VOID +EFIAPI +VmgInit ( + IN OUT GHCB *Ghcb + ); + +/** + 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 + +**/ +VOID +EFIAPI +VmgDone ( + IN OUT GHCB *Ghcb + ); + +/** + 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 + ); + +#endif diff --git a/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c new file mode 100644 index 0000000000..bb265e1700 --- /dev/null +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.c @@ -0,0 +1,121 @@ +/** @file + VMGEXIT Base Support Library. + + Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.
+ SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include +#include +#include + +/** + 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. + + The base library function does nothing. + + @param[in, out] Ghcb A pointer to the GHCB + +**/ +VOID +EFIAPI +VmgInit ( + IN OUT GHCB *Ghcb + ) +{ +} + +/** + Perform post-VMGEXIT cleanup. + + Performs the necessary steps to cleanup after invoking VMGEXIT. Must be + called after obtaining needed fields within the GHCB. + + The base library function does nothing. + + @param[in, out] Ghcb A pointer to the GHCB + +**/ +VOID +EFIAPI +VmgDone ( + IN OUT GHCB *Ghcb + ) +{ +} + +/** + 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 0000000000..d8770a21c3 --- /dev/null +++ b/UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf @@ -0,0 +1,27 @@ +## @file +# VMGEXIT Support Library. +# +# Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.
+# SPDX-License-Identifier: BSD-2-Clause-Patent +# +## + +[Defines] + INF_VERSION = 0x00010005 + BASE_NAME = VmgExitLibNull + MODULE_UNI_FILE = VmgExitLibNull.uni + FILE_GUID = 3cd7368f-ef9b-4a9b-9571-2ed93813677e + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = VmgExitLib + +[Sources.common] + VmgExitLibNull.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 0000000000..8639bc0e8c --- /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.
+// 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 d52912ddca..17228cb5a8 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 + [Guids] gUefiCpuPkgTokenSpaceGuid = { 0xac05bf33, 0x995a, 0x4ed4, { 0xaa, 0xb8, 0xef, 0x7a, 0xe8, 0xf, 0x5c, 0xb0 }} gMsegSmramGuid = { 0x5802bce4, 0xeeee, 0x4e33, { 0xa1, 0x30, 0xeb, 0xad, 0x27, 0xf0, 0xe4, 0x39 }} diff --git a/UefiCpuPkg/UefiCpuPkg.dsc b/UefiCpuPkg/UefiCpuPkg.dsc index 964720048d..b2b6d78a71 100644 --- a/UefiCpuPkg/UefiCpuPkg.dsc +++ b/UefiCpuPkg/UefiCpuPkg.dsc @@ -56,6 +56,7 @@ PeCoffGetEntryPointLib|MdePkg/Library/BasePeCoffGetEntryPointLib/BasePeCoffGetEntryPointLib.inf PeCoffExtraActionLib|MdePkg/Library/BasePeCoffExtraActionLibNull/BasePeCoffExtraActionLibNull.inf TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf + VmgExitLib|UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf [LibraryClasses.common.SEC] PlatformSecLib|UefiCpuPkg/Library/PlatformSecLibNull/PlatformSecLibNull.inf @@ -143,6 +144,7 @@ UefiCpuPkg/Library/SmmCpuPlatformHookLibNull/SmmCpuPlatformHookLibNull.inf UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf + UefiCpuPkg/Library/VmgExitLibNull/VmgExitLibNull.inf UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationPei.inf UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationSmm.inf UefiCpuPkg/SecCore/SecCore.inf -- 2.39.2