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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
commitf215e02bf85f68d3a6106c2a1f4f7f063f819064 (patch)
tree6bb5b92c046312c4e95ac2620b10ddf482d3fa8b /src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe
parentInitial commit. (diff)
downloadvirtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.tar.xz
virtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.zip
Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe')
-rw-r--r--src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.c137
-rw-r--r--src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.inf47
2 files changed, 184 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.c b/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.c
new file mode 100644
index 00000000..92ed4715
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.c
@@ -0,0 +1,137 @@
+/** @file
+
+ AMD Sev Dxe driver. This driver is dispatched early in DXE, due to being list
+ in APRIORI. It clears C-bit from MMIO and NonExistent Memory space when SEV
+ is enabled.
+
+ Copyright (c) 2017 - 2020, AMD Inc. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <IndustryStandard/Q35MchIch9.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/MemEncryptSevLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/PcdLib.h>
+
+EFI_STATUS
+EFIAPI
+AmdSevDxeEntryPoint (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_GCD_MEMORY_SPACE_DESCRIPTOR *AllDescMap;
+ UINTN NumEntries;
+ UINTN Index;
+
+ //
+ // Do nothing when SEV is not enabled
+ //
+ if (!MemEncryptSevIsEnabled ()) {
+ return EFI_UNSUPPORTED;
+ }
+
+ //
+ // Iterate through the GCD map and clear the C-bit from MMIO and NonExistent
+ // memory space. The NonExistent memory space will be used for mapping the
+ // MMIO space added later (eg PciRootBridge). By clearing both known MMIO and
+ // NonExistent memory space can gurantee that current and furture MMIO adds
+ // will have C-bit cleared.
+ //
+ Status = gDS->GetMemorySpaceMap (&NumEntries, &AllDescMap);
+ if (!EFI_ERROR (Status)) {
+ for (Index = 0; Index < NumEntries; Index++) {
+ CONST EFI_GCD_MEMORY_SPACE_DESCRIPTOR *Desc;
+
+ Desc = &AllDescMap[Index];
+ if (Desc->GcdMemoryType == EfiGcdMemoryTypeMemoryMappedIo ||
+ Desc->GcdMemoryType == EfiGcdMemoryTypeNonExistent) {
+ Status = MemEncryptSevClearPageEncMask (
+ 0,
+ Desc->BaseAddress,
+ EFI_SIZE_TO_PAGES (Desc->Length),
+ FALSE
+ );
+ ASSERT_EFI_ERROR (Status);
+ }
+ }
+
+ FreePool (AllDescMap);
+ }
+
+ //
+ // If PCI Express is enabled, the MMCONFIG area has been reserved, rather
+ // than marked as MMIO, and so the C-bit won't be cleared by the above walk
+ // through the GCD map. Check for the MMCONFIG area and clear the C-bit for
+ // the range.
+ //
+ if (PcdGet16 (PcdOvmfHostBridgePciDevId) == INTEL_Q35_MCH_DEVICE_ID) {
+ Status = MemEncryptSevClearPageEncMask (
+ 0,
+ FixedPcdGet64 (PcdPciExpressBaseAddress),
+ EFI_SIZE_TO_PAGES (SIZE_256MB),
+ FALSE
+ );
+
+ ASSERT_EFI_ERROR (Status);
+ }
+
+ //
+ // When SMM is enabled, clear the C-bit from SMM Saved State Area
+ //
+ // NOTES: The SavedStateArea address cleared here is before SMBASE
+ // relocation. Currently, we do not clear the SavedStateArea address after
+ // SMBASE is relocated due to the following reasons:
+ //
+ // 1) Guest BIOS never access the relocated SavedStateArea.
+ //
+ // 2) The C-bit works on page-aligned address, but the SavedStateArea
+ // address is not a page-aligned. Theoretically, we could roundup the address
+ // and clear the C-bit of aligned address but looking carefully we found
+ // that some portion of the page contains code -- which will causes a bigger
+ // issues for SEV guest. When SEV is enabled, all the code must be encrypted
+ // otherwise hardware will cause trap.
+ //
+ // We restore the C-bit for this SMM Saved State Area after SMBASE relocation
+ // is completed (See OvmfPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c).
+ //
+ if (FeaturePcdGet (PcdSmmSmramRequire)) {
+ UINTN MapPagesBase;
+ UINTN MapPagesCount;
+
+ Status = MemEncryptSevLocateInitialSmramSaveStateMapPages (
+ &MapPagesBase,
+ &MapPagesCount
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Although these pages were set aside (i.e., allocated) by PlatformPei, we
+ // could be after a warm reboot from the OS. Don't leak any stale OS data
+ // to the hypervisor.
+ //
+ ZeroMem ((VOID *)MapPagesBase, EFI_PAGES_TO_SIZE (MapPagesCount));
+
+ Status = MemEncryptSevClearPageEncMask (
+ 0, // Cr3BaseAddress -- use current CR3
+ MapPagesBase, // BaseAddress
+ MapPagesCount, // NumPages
+ TRUE // Flush
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: MemEncryptSevClearPageEncMask(): %r\n",
+ __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.inf b/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.inf
new file mode 100644
index 00000000..5343e289
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/OvmfPkg/AmdSevDxe/AmdSevDxe.inf
@@ -0,0 +1,47 @@
+#/** @file
+#
+# Driver clears the encryption attribute from MMIO regions when SEV is enabled
+#
+# Copyright (c) 2017 - 2020, AMD Inc. All rights reserved.<BR>
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#**/
+
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = AmdSevDxe
+ FILE_GUID = 2ec9da37-ee35-4de9-86c5-6d9a81dc38a7
+ MODULE_TYPE = DXE_DRIVER
+ VERSION_STRING = 1.0
+ ENTRY_POINT = AmdSevDxeEntryPoint
+
+[Sources]
+ AmdSevDxe.c
+
+[Packages]
+ MdeModulePkg/MdeModulePkg.dec
+ MdePkg/MdePkg.dec
+ OvmfPkg/OvmfPkg.dec
+
+[LibraryClasses]
+ BaseLib
+ BaseMemoryLib
+ DebugLib
+ DxeServicesTableLib
+ MemEncryptSevLib
+ MemoryAllocationLib
+ PcdLib
+ UefiDriverEntryPoint
+
+[Depex]
+ TRUE
+
+[FeaturePcd]
+ gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire
+
+[FixedPcd]
+ gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
+
+[Pcd]
+ gUefiOvmfPkgTokenSpaceGuid.PcdOvmfHostBridgePciDevId