CPU microcode reported wrong in /proc/cpuinfo

Brian Inglis Brian.Inglis@SystematicSw.ab.ca
Thu Jul 16 20:13:49 GMT 2020

On 2020-07-16 13:46, Brian Inglis wrote:
> On 2020-07-16 08:56, Lavrentiev, Anton (NIH/NLM/NCBI) [C] via Cygwin wrote:
> It may be possible that Windows executes a CPUID instruction, and then reads MSR

Intel states CPUID of leaf EAX = 1, so not reading that leaf may not update MSR.

> 8BH IA32_BIOS_SIGN_ID to get the current value, without first preloading the MSR
> with zero, and rather than interpreting the zero result as unchanged, just
> reports that value.
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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