diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c index db68e1316e..67ad9a4c07 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c @@ -729,8 +729,8 @@ PiCpuSmmEntry ( DEBUG ((DEBUG_INFO, "PcdControlFlowEnforcementPropertyMask = %d\n", PcdGet32 (PcdControlFlowEnforcementPropertyMask))); if (PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) { - AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL); - if (RegEax > CPUID_EXTENDED_FUNCTION) { + AsmCpuid (CPUID_SIGNATURE, &RegEax, NULL, NULL, NULL); + if (RegEax >= CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS) { AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, &RegEdx); DEBUG ((DEBUG_INFO, "CPUID[7/0] ECX - 0x%08x\n", RegEcx)); DEBUG ((DEBUG_INFO, " CET_SS - 0x%08x\n", RegEcx & CPUID_CET_SS)); @@ -747,6 +747,9 @@ PiCpuSmmEntry ( AsmCpuidEx(CPUID_EXTENDED_STATE, 12, &RegEax, NULL, &RegEcx, NULL); DEBUG ((DEBUG_INFO, "CPUID[D/12] EAX - 0x%08x, ECX - 0x%08x\n", RegEax, RegEcx)); } + } else { + mCetSupported = FALSE; + PatchInstructionX86(mPatchCetSupported, mCetSupported, 1); } } else { mCetSupported = FALSE; diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c index d7ed9ab7a7..972bdc2859 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c @@ -985,13 +985,14 @@ CheckFeatureSupported ( MSR_IA32_MISC_ENABLE_REGISTER MiscEnableMsr; if ((PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) && mCetSupported) { - AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL); - if (RegEax <= CPUID_EXTENDED_FUNCTION) { - mCetSupported = FALSE; - PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); - } - AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, NULL); - if ((RegEcx & CPUID_CET_SS) == 0) { + AsmCpuid (CPUID_SIGNATURE, &RegEax, NULL, NULL, NULL); + if (RegEax >= CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS) { + AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, NULL); + if ((RegEcx & CPUID_CET_SS) == 0) { + mCetSupported = FALSE; + PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); + } + } else { mCetSupported = FALSE; PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); }