From 6ced1e91eff13dae1bfba95734e2b34a73601db2 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Fri, 8 Mar 2024 07:31:53 -0800 Subject: [PATCH] Ovmfpkg/AmdSvsmLib: Create AmdSvsmLib to handle SVSM related services BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654 Add initial support for the new AmdSvsmLib library to OvmfPkg. The initial implementation fully implements the library interfaces. The SVSM presence check, AmdSvsmIsSvsmPresent(), determines the presence of an SVSM by checking if an SVSM has been advertised in the SEV-SNP Secrets Page. The VMPL API, AmdSvsmSnpGetVmpl(), returns the VMPL level at which OVMF is currently running. The CAA API, AmdSvsmSnpGetCaa(), returns the Calling Area Address when an SVSM is present, 0 otherwise. The PVALIDATE API, AmdSvsmSnpPvalidate(), copies the PVALIDATE logic from the BaseMemEncryptSevLib library for the initial implementation. The BaseMemEncryptSevLib library will be changed to use this new API so that the decision as to whether the SVSM is needed to perform the operation can be isolated to this library. The VMSA API, AmdSvsmSnpVmsaRmpAdjust(), copies the RMPUPDATE logic from the MpInitLib library for the initial implementation. The MpInitLib library will be changed to use this new API so that the decision as to whether the SVSM is needed to perform the operation can be isolated to this library. Cc: Anatol Belski Cc: Ard Biesheuvel Cc: Erdem Aktas Cc: Gerd Hoffmann Cc: Jianyong Wu Cc: Jiewen Yao Cc: Laszlo Ersek Cc: Michael Roth Cc: Min Xu Signed-off-by: Tom Lendacky Acked-by: Gerd Hoffmann --- OvmfPkg/AmdSev/AmdSevX64.dsc | 2 +- OvmfPkg/CloudHv/CloudHvX64.dsc | 2 +- OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c | 267 ++++++++++++++++++++++ OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf | 38 +++ OvmfPkg/Microvm/MicrovmX64.dsc | 2 +- OvmfPkg/OvmfPkgX64.dsc | 2 +- 6 files changed, 309 insertions(+), 4 deletions(-) create mode 100644 OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c create mode 100644 OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf diff --git a/OvmfPkg/AmdSev/AmdSevX64.dsc b/OvmfPkg/AmdSev/AmdSevX64.dsc index 140c4208f5..a7540bb636 100644 --- a/OvmfPkg/AmdSev/AmdSevX64.dsc +++ b/OvmfPkg/AmdSev/AmdSevX64.dsc @@ -204,7 +204,7 @@ !include OvmfPkg/Include/Dsc/ShellLibs.dsc.inc [LibraryClasses.common] - AmdSvsmLib|UefiCpuPkg/Library/AmdSvsmLibNull/AmdSvsmLibNull.inf + AmdSvsmLib|OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf CcExitLib|OvmfPkg/Library/CcExitLib/CcExitLib.inf TdxLib|MdePkg/Library/TdxLib/TdxLib.inf diff --git a/OvmfPkg/CloudHv/CloudHvX64.dsc b/OvmfPkg/CloudHv/CloudHvX64.dsc index 4dad0a36e7..b1911d6ab4 100644 --- a/OvmfPkg/CloudHv/CloudHvX64.dsc +++ b/OvmfPkg/CloudHv/CloudHvX64.dsc @@ -242,7 +242,7 @@ !include OvmfPkg/Include/Dsc/OvmfTpmLibs.dsc.inc [LibraryClasses.common] - AmdSvsmLib|UefiCpuPkg/Library/AmdSvsmLibNull/AmdSvsmLibNull.inf + AmdSvsmLib|OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf CcExitLib|OvmfPkg/Library/CcExitLib/CcExitLib.inf TdxLib|MdePkg/Library/TdxLib/TdxLib.inf diff --git a/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c new file mode 100644 index 0000000000..861bf9591a --- /dev/null +++ b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c @@ -0,0 +1,267 @@ +/** @file + SVSM Support Library. + + Copyright (C) 2024, Advanced Micro Devices, Inc. All rights reserved.
+ SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include +#include +#include +#include +#include + +#define PAGES_PER_2MB_ENTRY 512 + +/** + Issue a GHCB termination request for termination. + + Request termination using the GHCB MSR protocol. + +**/ +STATIC +VOID +SnpTerminate ( + VOID + ) +{ + MSR_SEV_ES_GHCB_REGISTER Msr; + + // + // Use the GHCB MSR Protocol to request termination by the hypervisor + // + Msr.Uint64 = 0; + Msr.GhcbTerminate.Function = GHCB_INFO_TERMINATE_REQUEST; + Msr.GhcbTerminate.ReasonCodeSet = GHCB_TERMINATE_GHCB; + Msr.GhcbTerminate.ReasonCode = GHCB_TERMINATE_GHCB_GENERAL; + AsmWriteMsr64 (MSR_SEV_ES_GHCB, Msr.Uint64); + + AsmVmgExit (); + + ASSERT (FALSE); + CpuDeadLoop (); +} + +/** + Report the presence of an Secure Virtual Services Module (SVSM). + + Determines the presence of an SVSM. + + @retval TRUE An SVSM is present + @retval FALSE An SVSM is not present + +**/ +BOOLEAN +EFIAPI +AmdSvsmIsSvsmPresent ( + VOID + ) +{ + SVSM_INFORMATION *SvsmInfo; + + SvsmInfo = (SVSM_INFORMATION *)(UINTN)PcdGet32 (PcdOvmfSnpSecretsBase); + + return (SvsmInfo != NULL && SvsmInfo->SvsmSize != 0); +} + +/** + Report the VMPL level at which the SEV-SNP guest is running. + + Determines the VMPL level at which the guest is running. If an SVSM is + not present, then it must be VMPL0, otherwise return what is reported + by the SVSM. + + @return The VMPL level + +**/ +UINT8 +EFIAPI +AmdSvsmSnpGetVmpl ( + VOID + ) +{ + SVSM_INFORMATION *SvsmInfo; + + SvsmInfo = (SVSM_INFORMATION *)(UINTN)PcdGet32 (PcdOvmfSnpSecretsBase); + + return AmdSvsmIsSvsmPresent () ? SvsmInfo->SvsmGuestVmpl : 0; +} + +/** + Report the Calling Area address (CAA) for the BSP of the SEV-SNP guest. + + If an SVSM is present, the CAA for the BSP is returned. + + @return The CAA + +**/ +UINT64 +EFIAPI +AmdSvsmSnpGetCaa ( + VOID + ) +{ + SVSM_INFORMATION *SvsmInfo; + + SvsmInfo = (SVSM_INFORMATION *)(UINTN)PcdGet32 (PcdOvmfSnpSecretsBase); + + return AmdSvsmIsSvsmPresent () ? SvsmInfo->SvsmCaa : 0; +} + +/** + Perform a native PVALIDATE operation for the page ranges specified. + + Validate or rescind the validation of the specified pages. + + @param[in] Info Pointer to a page state change structure + +**/ +STATIC +VOID +BasePvalidate ( + IN SNP_PAGE_STATE_CHANGE_INFO *Info + ) +{ + UINTN RmpPageSize; + UINTN StartIndex; + UINTN EndIndex; + UINTN Index; + UINTN Ret; + EFI_PHYSICAL_ADDRESS Address; + BOOLEAN Validate; + + StartIndex = Info->Header.CurrentEntry; + EndIndex = Info->Header.EndEntry; + + for ( ; StartIndex <= EndIndex; StartIndex++) { + // + // Get the address and the page size from the Info. + // + Address = ((EFI_PHYSICAL_ADDRESS)Info->Entry[StartIndex].GuestFrameNumber) << EFI_PAGE_SHIFT; + RmpPageSize = Info->Entry[StartIndex].PageSize; + Validate = Info->Entry[StartIndex].Operation == SNP_PAGE_STATE_PRIVATE; + + Ret = AsmPvalidate (RmpPageSize, Validate, Address); + + // + // If we fail to validate due to size mismatch then try with the + // smaller page size. This senario will occur if the backing page in + // the RMP entry is 4K and we are validating it as a 2MB. + // + if ((Ret == PVALIDATE_RET_SIZE_MISMATCH) && (RmpPageSize == PvalidatePageSize2MB)) { + for (Index = 0; Index < PAGES_PER_2MB_ENTRY; Index++) { + Ret = AsmPvalidate (PvalidatePageSize4K, Validate, Address); + if (Ret) { + break; + } + + Address = Address + EFI_PAGE_SIZE; + } + } + + // + // If validation failed then do not continue. + // + if (Ret) { + DEBUG (( + DEBUG_ERROR, + "%a:%a: Failed to %a address 0x%Lx Error code %d\n", + gEfiCallerBaseName, + __func__, + Validate ? "Validate" : "Invalidate", + Address, + Ret + )); + + SnpTerminate (); + } + } +} + +/** + Perform a PVALIDATE operation for the page ranges specified. + + Validate or rescind the validation of the specified pages. + + @param[in] Info Pointer to a page state change structure + +**/ +VOID +EFIAPI +AmdSvsmSnpPvalidate ( + IN SNP_PAGE_STATE_CHANGE_INFO *Info + ) +{ + BasePvalidate (Info); +} + +/** + Perform a native RMPADJUST operation to alter the VMSA setting of a page. + + Add or remove the VMSA attribute for a page. + + @param[in] Vmsa Pointer to an SEV-ES save area page + @param[in] SetVmsa Boolean indicator as to whether to set or + or clear the VMSA setting for the page + + @retval EFI_SUCCESS RMPADJUST operation successful + @retval EFI_INVALID_PARAMETER RMPADJUST operation failed, an invalid + parameter was supplied + +**/ +STATIC +EFI_STATUS +BaseVmsaRmpAdjust ( + IN SEV_ES_SAVE_AREA *Vmsa, + IN BOOLEAN SetVmsa + ) +{ + UINT64 Rdx; + UINT32 Ret; + + // + // The RMPADJUST instruction is used to set or clear the VMSA bit for a + // page. The VMSA change is only made when running at VMPL0 and is ignored + // otherwise. If too low a target VMPL is specified, the instruction can + // succeed without changing the VMSA bit when not running at VMPL0. Using a + // target VMPL level of 1, RMPADJUST will return a FAIL_PERMISSION error if + // not running at VMPL0, thus ensuring that the VMSA bit is set appropriately + // when no error is returned. + // + Rdx = 1; + if (SetVmsa) { + Rdx |= RMPADJUST_VMSA_PAGE_BIT; + } + + Ret = AsmRmpAdjust ((UINT64)(UINTN)Vmsa, 0, Rdx); + + return (Ret == 0) ? EFI_SUCCESS : EFI_INVALID_PARAMETER; +} + +/** + Perform an RMPADJUST operation to alter the VMSA setting of a page. + + Add or remove the VMSA attribute for a page. + + @param[in] Vmsa Pointer to an SEV-ES save area page + @param[in] ApicId APIC ID associated with the VMSA + @param[in] SetVmsa Boolean indicator as to whether to set or + or clear the VMSA setting for the page + + @retval EFI_SUCCESS RMPADJUST operation successful + @retval EFI_UNSUPPORTED Operation is not supported + @retval EFI_INVALID_PARAMETER RMPADJUST operation failed, an invalid + parameter was supplied + +**/ +EFI_STATUS +EFIAPI +AmdSvsmSnpVmsaRmpAdjust ( + IN SEV_ES_SAVE_AREA *Vmsa, + IN UINT32 ApicId, + IN BOOLEAN SetVmsa + ) +{ + return BaseVmsaRmpAdjust (Vmsa, SetVmsa); +} diff --git a/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf new file mode 100644 index 0000000000..cfd2663adc --- /dev/null +++ b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf @@ -0,0 +1,38 @@ +## @file +# CcExitLib Library. +# +# Copyright (C) 2024, Advanced Micro Devices, Inc. All rights reserved.
+# SPDX-License-Identifier: BSD-2-Clause-Patent +# +## + +[Defines] + INF_VERSION = 1.29 + BASE_NAME = AmdSvsmLib + FILE_GUID = 288e3588-87d8-4c2c-b568-bf900de0fb36 + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = AmdSvsmLib + +# +# The following information is for reference only and not required by the build tools. +# +# VALID_ARCHITECTURES = X64 +# + +[Sources.common] + AmdSvsmLib.c + +[Packages] + MdePkg/MdePkg.dec + OvmfPkg/OvmfPkg.dec + UefiCpuPkg/UefiCpuPkg.dec + +[LibraryClasses] + BaseLib + BaseMemoryLib + DebugLib + +[Pcd] + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize diff --git a/OvmfPkg/Microvm/MicrovmX64.dsc b/OvmfPkg/Microvm/MicrovmX64.dsc index cc84ee3c29..1f2f8b5bb6 100644 --- a/OvmfPkg/Microvm/MicrovmX64.dsc +++ b/OvmfPkg/Microvm/MicrovmX64.dsc @@ -246,7 +246,7 @@ !include OvmfPkg/Include/Dsc/ShellLibs.dsc.inc [LibraryClasses.common] - AmdSvsmLib|UefiCpuPkg/Library/AmdSvsmLibNull/AmdSvsmLibNull.inf + AmdSvsmLib|OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf CcExitLib|OvmfPkg/Library/CcExitLib/CcExitLib.inf SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc index d0460178eb..f2edd3bbc0 100644 --- a/OvmfPkg/OvmfPkgX64.dsc +++ b/OvmfPkg/OvmfPkgX64.dsc @@ -268,7 +268,7 @@ !include OvmfPkg/Include/Dsc/ShellLibs.dsc.inc [LibraryClasses.common] - AmdSvsmLib|UefiCpuPkg/Library/AmdSvsmLibNull/AmdSvsmLibNull.inf + AmdSvsmLib|OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.inf BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf CcExitLib|OvmfPkg/Library/CcExitLib/CcExitLib.inf TdxLib|MdePkg/Library/TdxLib/TdxLib.inf