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UefiCpuPkg/CpuMpPei: Dump message if microcode signature not matched

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Verification microcode signature is one enhancement and not one requirement from
IA32 SDM. This update is just to dump debug message instead of ASSERT() if the
updated microcode signature does not match the loaded microcode signature.

Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Giri P Mudusuru <giri.p.mudusuru@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Giri P Mudusuru <giri.p.mudusuru@intel.com>
This commit is contained in:
Jeff Fan
2016-07-01 14:52:12 +08:00
parent 46fd118219
commit 719ff8cf3e
4 changed files with 31 additions and 25 deletions
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33
UefiCpuPkg/CpuMpPei/Microcode.c
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@@ -36,10 +36,11 @@ GetCurrentMicrocodeSignature (
/**
Detect whether specified processor can find matching microcode patch and load it.
@param PeiCpuMpData Pointer to PEI CPU MP Data
**/
VOID
MicrocodeDetect (
VOID
IN PEI_CPU_MP_DATA *PeiCpuMpData
)
{
UINT64 MicrocodePatchAddress;
@@ -187,25 +188,29 @@ MicrocodeDetect (
MicrocodeEntryPoint = (EFI_CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + TotalSize);
} while (((UINTN) MicrocodeEntryPoint < MicrocodeEnd));
if (LatestRevision > 0) {
if (LatestRevision > CurrentRevision) {
//
// BIOS only authenticate updates that contain a numerically larger revision
// than the currently loaded revision, where Current Signature < New Update
// Revision. A processor with no loaded update is considered to have a
// revision equal to zero.
//
if (LatestRevision > GetCurrentMicrocodeSignature ()) {
AsmWriteMsr64 (
EFI_MSR_IA32_BIOS_UPDT_TRIG,
(UINT64) (UINTN) MicrocodeInfo.MicrocodeData
);
//
// Get and verify new microcode signature
//
ASSERT (LatestRevision == GetCurrentMicrocodeSignature ());
MicrocodeInfo.Load = TRUE;
} else {
MicrocodeInfo.Load = FALSE;
AsmWriteMsr64 (
EFI_MSR_IA32_BIOS_UPDT_TRIG,
(UINT64) (UINTN) MicrocodeInfo.MicrocodeData
);
//
// Get and check new microcode signature
//
CurrentRevision = GetCurrentMicrocodeSignature ();
if (CurrentRevision != LatestRevision) {
AcquireSpinLock(&PeiCpuMpData->MpLock);
DEBUG ((EFI_D_ERROR, "Updated microcode signature [0x%08x] does not match \
loaded microcode signature [0x%08x]\n", CurrentRevision, LatestRevision));
ReleaseSpinLock(&PeiCpuMpData->MpLock);
}
MicrocodeInfo.Load = TRUE;
} else {
MicrocodeInfo.Load = FALSE;
}
}