mirror of https://github.com/acidanthera/audk.git
362654246a
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108 Protect the GHCB backup pages used by an SEV-ES guest when S3 is supported. Regarding the lifecycle of the GHCB backup pages: PcdOvmfSecGhcbBackupBase (a) when and how it is initialized after first boot of the VM If SEV-ES is enabled, the GHCB backup pages are initialized when a nested #VC is received during the SEC phase [OvmfPkg/Library/VmgExitLib/SecVmgExitVcHandler.c]. (b) how it is protected from memory allocations during DXE If S3 and SEV-ES are enabled, then InitializeRamRegions() [OvmfPkg/PlatformPei/MemDetect.c] protects the ranges with an AcpiNVS memory allocation HOB, in PEI. If S3 is disabled, then these ranges are not protected. PEI switches to the GHCB backup pages in permanent PEI memory and DXE will use these PEI GHCB backup pages, so we don't have to preserve PcdOvmfSecGhcbBackupBase. (c) how it is protected from the OS If S3 is enabled, then (b) reserves it from the OS too. If S3 is disabled, then the range needs no protection. (d) how it is accessed on the S3 resume path It is rewritten same as in (a), which is fine because (b) reserved it. (e) how it is accessed on the warm reset path It is rewritten same as in (a). Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@arm.com> Cc: Anthony Perard <anthony.perard@citrix.com> Cc: Julien Grall <julien@xen.org> Cc: Brijesh Singh <brijesh.singh@amd.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <119102a3d14caa70d81aee334a2e0f3f925e1a60.1610045305.git.thomas.lendacky@amd.com> |
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| .. | ||
| AmdSev.c | ||
| ClearCache.c | ||
| Cmos.c | ||
| Cmos.h | ||
| FeatureControl.c | ||
| Fv.c | ||
| MemDetect.c | ||
| MemTypeInfo.c | ||
| Platform.c | ||
| Platform.h | ||
| PlatformPei.inf | ||
| Xen.c | ||
| Xen.h | ||