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MdeModulePkg/DxeIplPeim: Support GHCB pages when creating page tables

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BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198

GHCB pages must be mapped as shared pages, so modify the process of
creating identity mapped pagetable entries so that GHCB entries are
created without the encryption bit set. The GHCB range consists of
two pages per CPU, the first being the GHCB and the second being a
per-CPU variable page. Only the GHCB page is mapped as shared.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Acked-by: Hao A Wu <hao.a.wu@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Tom Lendacky
2020-08-12 15:21:35 -05:00
committed by mergify[bot]
parent 1c0eb91503
commit b098f5e9e9
5 changed files with 70 additions and 16 deletions
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11
MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c
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@@ -35,6 +35,8 @@ HandOffToDxeCore (
UINT32 Index;
EFI_VECTOR_HANDOFF_INFO *VectorInfo;
EFI_PEI_VECTOR_HANDOFF_INFO_PPI *VectorHandoffInfoPpi;
VOID *GhcbBase;
UINTN GhcbSize;
//
// Clear page 0 and mark it as allocated if NULL pointer detection is enabled.
@@ -81,12 +83,19 @@ HandOffToDxeCore (
TopOfStack = (VOID *) ((UINTN) BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);
TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
//
// Get the address and size of the GHCB pages
//
GhcbBase = (VOID *) PcdGet64 (PcdGhcbBase);
GhcbSize = PcdGet64 (PcdGhcbSize);
PageTables = 0;
if (FeaturePcdGet (PcdDxeIplBuildPageTables)) {
//
// Create page table and save PageMapLevel4 to CR3
//
PageTables = CreateIdentityMappingPageTables ((EFI_PHYSICAL_ADDRESS) (UINTN) BaseOfStack, STACK_SIZE);
PageTables = CreateIdentityMappingPageTables ((EFI_PHYSICAL_ADDRESS) (UINTN) BaseOfStack, STACK_SIZE,
(EFI_PHYSICAL_ADDRESS) (UINTN) GhcbBase, GhcbSize);
} else {
//
// Set NX for stack feature also require PcdDxeIplBuildPageTables be TRUE