Cpuid passthrough mutable fields#77
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olivereanderson merged 2 commits intocyberus-technology:gardenlinuxfrom Feb 23, 2026
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CPUID leaf 0x1 ECX[27] and 0x7 ECX[4] can change at runtime, hence it does not make sense to set their values in the CPU profile. Note that Section 21.1.5 of the Intel SDM Vol.1, mentions a few other mutable CPUID fields as well, but we deem it safe to leave them as the are. Signed-off-by: Oliver Anderson <oliver.anderson@cyberus-technology.de> On-behalf-of: SAP oliver.anderson@sap.com
We regenerate the CPU profiles to take the policy changes from the previous commit into account. Signed-off-by: Oliver Anderson <oliver.anderson@cyberus-technology.de> On-behalf-of: SAP oliver.anderson@sap.com
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As I was reading through the Intel SDM I happened to stumble upon a section about runtime mutable CPUID fields
(Section 21.1.5 in Vol.1). This made me realize that we probably chose wrong policies for OSXSAVE and OSPKE.
There are a few more mutable fields mentioned in the manual, but we already spent some time finding and deliberately setting appropriate policies for those hence I think they can be left as is.