diff options
| author | Sophia Wolf <phiawolf@google.com> | 2022-11-08 16:46:14 +0000 |
|---|---|---|
| committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2023-01-12 16:03:30 +0000 |
| commit | 59aa48bb7ddae082b0e56f57a7c856c9628b72de (patch) | |
| tree | c77510b9c15277e305bcd191b6004e60886626c8 | |
| parent | e5ec3ba409b5baa9cf429cc25fdf3c8d1b8dcef0 (diff) | |
| download | edk2-59aa48bb7ddae082b0e56f57a7c856c9628b72de.tar.gz | |
OvmfPkg: Realize EfiMemoryAcceptProtocol in AmdSevDxe
When a guest OS does not support unaccepted memory, the unaccepted
memory must be accepted before returning a memory map to the caller.
EfiMemoryAcceptProtocol is defined in MdePkg and is implemented /
Installed in AmdSevDxe for AMD SEV-SNP memory acceptance.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
Signed-off-by: Dionna Glaze <dionnaglaze@google.com>
Message-Id: <20221108164616.3251967-2-dionnaglaze@google.com>
| -rw-r--r-- | OvmfPkg/AmdSevDxe/AmdSevDxe.c | 55 | ||||
| -rw-r--r-- | OvmfPkg/AmdSevDxe/AmdSevDxe.inf | 3 | ||||
| -rw-r--r-- | OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c | 24 |
3 files changed, 74 insertions, 8 deletions
diff --git a/OvmfPkg/AmdSevDxe/AmdSevDxe.c b/OvmfPkg/AmdSevDxe/AmdSevDxe.c index 662d3c4ccb..f7600c3c81 100644 --- a/OvmfPkg/AmdSevDxe/AmdSevDxe.c +++ b/OvmfPkg/AmdSevDxe/AmdSevDxe.c @@ -20,6 +20,7 @@ #include <Library/UefiBootServicesTableLib.h>
#include <Guid/ConfidentialComputingSevSnpBlob.h>
#include <Library/PcdLib.h>
+#include <Protocol/MemoryAccept.h>
STATIC CONFIDENTIAL_COMPUTING_SNP_BLOB_LOCATION mSnpBootDxeTable = {
SIGNATURE_32 ('A', 'M', 'D', 'E'),
@@ -31,6 +32,40 @@ STATIC CONFIDENTIAL_COMPUTING_SNP_BLOB_LOCATION mSnpBootDxeTable = { FixedPcdGet32 (PcdOvmfCpuidSize),
};
+STATIC EFI_HANDLE mAmdSevDxeHandle = NULL;
+
+#define IS_ALIGNED(x, y) ((((x) & ((y) - 1)) == 0))
+
+STATIC
+EFI_STATUS
+EFIAPI
+AmdSevMemoryAccept (
+ IN EDKII_MEMORY_ACCEPT_PROTOCOL *This,
+ IN EFI_PHYSICAL_ADDRESS StartAddress,
+ IN UINTN Size
+ )
+{
+ //
+ // The StartAddress must be page-aligned, and the Size must be a positive
+ // multiple of SIZE_4KB. Use an assert instead of returning an erros since
+ // this is an EDK2-internal protocol.
+ //
+ ASSERT (IS_ALIGNED (StartAddress, SIZE_4KB));
+ ASSERT (IS_ALIGNED (Size, SIZE_4KB));
+ ASSERT (Size != 0);
+
+ MemEncryptSevSnpPreValidateSystemRam (
+ StartAddress,
+ EFI_SIZE_TO_PAGES (Size)
+ );
+
+ return EFI_SUCCESS;
+}
+
+STATIC EDKII_MEMORY_ACCEPT_PROTOCOL mMemoryAcceptProtocol = {
+ AmdSevMemoryAccept
+};
+
EFI_STATUS
EFIAPI
AmdSevDxeEntryPoint (
@@ -147,11 +182,23 @@ AmdSevDxeEntryPoint ( }
}
- //
- // If its SEV-SNP active guest then install the CONFIDENTIAL_COMPUTING_SEV_SNP_BLOB.
- // It contains the location for both the Secrets and CPUID page.
- //
if (MemEncryptSevSnpIsEnabled ()) {
+ //
+ // Memory acceptance began being required in SEV-SNP, so install the
+ // memory accept protocol implementation for a SEV-SNP active guest.
+ //
+ Status = gBS->InstallProtocolInterface (
+ &mAmdSevDxeHandle,
+ &gEdkiiMemoryAcceptProtocolGuid,
+ EFI_NATIVE_INTERFACE,
+ &mMemoryAcceptProtocol
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // If its SEV-SNP active guest then install the CONFIDENTIAL_COMPUTING_SEV_SNP_BLOB.
+ // It contains the location for both the Secrets and CPUID page.
+ //
return gBS->InstallConfigurationTable (
&gConfidentialComputingSevSnpBlobGuid,
&mSnpBootDxeTable
diff --git a/OvmfPkg/AmdSevDxe/AmdSevDxe.inf b/OvmfPkg/AmdSevDxe/AmdSevDxe.inf index 9acf860cf2..cd1b686c53 100644 --- a/OvmfPkg/AmdSevDxe/AmdSevDxe.inf +++ b/OvmfPkg/AmdSevDxe/AmdSevDxe.inf @@ -47,6 +47,9 @@ gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize
+[Protocols]
+ gEdkiiMemoryAcceptProtocolGuid
+
[Guids]
gConfidentialComputingSevSnpBlobGuid
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c index d3a95e4913..cbcdd46f52 100644 --- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c +++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/DxeSnpSystemRamValidate.c @@ -14,6 +14,7 @@ #include <Library/MemEncryptSevLib.h>
#include "SnpPageStateChange.h"
+#include "VirtualMemory.h"
/**
Pre-validate the system RAM when SEV-SNP is enabled in the guest VM.
@@ -29,12 +30,27 @@ MemEncryptSevSnpPreValidateSystemRam ( IN UINTN NumPages
)
{
+ EFI_STATUS Status;
+
if (!MemEncryptSevSnpIsEnabled ()) {
return;
}
- //
- // All the pre-validation must be completed in the PEI phase.
- //
- ASSERT (FALSE);
+ // DXE pre-validation may happen with the memory accept protocol.
+ // The protocol should only be called outside the prevalidated ranges
+ // that the PEI stage code explicitly skips. Specifically, only memory
+ // ranges that are classified as unaccepted.
+ if (BaseAddress >= SIZE_4GB) {
+ Status = InternalMemEncryptSevCreateIdentityMap1G (
+ 0,
+ BaseAddress,
+ EFI_PAGES_TO_SIZE (NumPages)
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ }
+
+ InternalSetPageState (BaseAddress, NumPages, SevSnpPagePrivate, TRUE);
}
|