igvmbuilder: configure XCR0 as expected in CPUID tables #511
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A recent change to the SVSM kernel requires XCR0 to match the value `1` when looking for CPUID[EAX=0Dh] leaves. However, the IGVM file builder was populating the CPUID template with XCR0=0, resulting in a mismatch when the CPUID lookup was attempted. This change sets XCR0=1 for the extended leaves in the CPUID template in the IGVM file so the constructed table matches the expected value at lookup time. Signed-off-by: Jon Lange <[email protected]>
The set of available extended features (XFEM/XCR0) is enumerated by CPUID[EAX=0Dh,ECX=00h].EAX. The set of available XSAVE features (e.g. XSAVEOPT, XSAVEC) is enumerated by CPUID[EAX=0Dh,ECX=01h].EAX. The previous code had the CPUID detection inverted. Signed-off-by: Jon Lange <[email protected]>
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A recent change to the SVSM kernel requires XCR0 to match the value
1when looking for CPUID[EAX=0Dh] leaves. However, the IGVM file builder was populating the CPUID template with XCR0=0, resulting in a mismatch when the CPUID lookup was attempted. This change sets XCR0=1 for the extended leaves in the CPUID template in the IGVM file so the constructed table matches the expected value at lookup time.