REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1020
The following Microcode payload format is define in SDM spec.
Payload: |MicrocodeHeader|MicrocodeBinary|ExtendedHeader|ExtendedTable|.
When we verify the CheckSum32 with ExtendedTable, we should use the fields
of ExtendedTable to replace corresponding fields in MicrocodeHeader,
and then calculate the CheckSum32 with MicrocodeHeader+MicrocodeBinary.
This patch already verified on ICL platform.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chen A Chen <chen.a.c...@intel.com>
Cc: Ray Ni <ray...@intel.com>
Cc: Eric Dong <eric.d...@intel.com>
---
UefiCpuPkg/Library/MpInitLib/Microcode.c | 38 ++++++++++++++++++++++++--------
1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c
b/UefiCpuPkg/Library/MpInitLib/Microcode.c
index d84344c6f5..38880cdbec 100644
--- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
+++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
@@ -57,6 +57,7 @@ MicrocodeDetect (
UINT32 LatestRevision;
UINTN TotalSize;
UINT32 CheckSum32;
+ UINT32 InCompleteCheckSum32;
BOOLEAN CorrectMicrocode;
VOID *MicrocodeData;
MSR_IA32_PLATFORM_ID_REGISTER PlatformIdMsr;
@@ -121,6 +122,26 @@ MicrocodeDetect (
MicrocodeData = NULL;
MicrocodeEnd = (UINTN) (CpuMpData->MicrocodePatchAddress +
CpuMpData->MicrocodePatchRegionSize);
MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (UINTN)
CpuMpData->MicrocodePatchAddress;
+
+ //
+ // To avoid double calculate checksum32 value.
+ // Save the CheckSum32 of the common parts in advance.
+ //
+ if (MicrocodeEntryPoint->DataSize == 0) {
+ InCompleteCheckSum32 = CalculateSum32 (
+ (UINT32 *) MicrocodeEntryPoint,
+ sizeof (CPU_MICROCODE_HEADER) + 2000
+ );
+ } else {
+ InCompleteCheckSum32 = CalculateSum32 (
+ (UINT32 *) MicrocodeEntryPoint,
+ sizeof (CPU_MICROCODE_HEADER) +
MicrocodeEntryPoint->DataSize
+ );
+ }
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
+
do {
//
// Check if the microcode is for the Cpu and the version is newer
@@ -137,14 +158,10 @@ MicrocodeDetect (
MicrocodeEntryPoint->UpdateRevision > LatestRevision &&
(MicrocodeEntryPoint->ProcessorFlags & (1 << PlatformId))
) {
- if (MicrocodeEntryPoint->DataSize == 0) {
- CheckSum32 = CalculateSum32 ((UINT32 *) MicrocodeEntryPoint, 2048);
- } else {
- CheckSum32 = CalculateSum32 (
- (UINT32 *) MicrocodeEntryPoint,
- MicrocodeEntryPoint->DataSize + sizeof
(CPU_MICROCODE_HEADER)
- );
- }
+ CheckSum32 = InCompleteCheckSum32;
+ CheckSum32 += MicrocodeEntryPoint->ProcessorSignature.Uint32;
+ CheckSum32 += MicrocodeEntryPoint->ProcessorFlags;
+ CheckSum32 += MicrocodeEntryPoint->Checksum;
if (CheckSum32 == 0) {
CorrectMicrocode = TRUE;
ProcessorFlags = MicrocodeEntryPoint->ProcessorFlags;
@@ -171,7 +188,10 @@ MicrocodeDetect (
ExtendedTableCount = ExtendedTableHeader->ExtendedSignatureCount;
ExtendedTable = (CPU_MICROCODE_EXTENDED_TABLE *)
(ExtendedTableHeader + 1);
for (Index = 0; Index < ExtendedTableCount; Index ++) {
- CheckSum32 = CalculateSum32 ((UINT32 *) ExtendedTable,
sizeof(CPU_MICROCODE_EXTENDED_TABLE));
+ CheckSum32 = InCompleteCheckSum32;
+ CheckSum32 += ExtendedTable->ProcessorSignature.Uint32;
+ CheckSum32 += ExtendedTable->ProcessorFlag;
+ CheckSum32 += ExtendedTable->Checksum;
if (CheckSum32 == 0) {
//
// Verify Header
--
2.16.2.windows.1
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