Re: [PATCH 6/7] KVM: x86: Ignore benign host accesses to "unsupported" PEBS and BTS MSRs

From: Vitaly Kuznetsov
Date: Tue Jun 14 2022 - 03:45:11 EST


Sean Christopherson <seanjc@xxxxxxxxxx> writes:

> Ignore host userspace reads and writes of '0' to PEBS and BTS MSRs that
> KVM reports in the MSR-to-save list, but the MSRs are ultimately
> unsupported. All MSRs in said list must be writable by userspace, e.g.
> if userspace sends the list back at KVM without filtering out the MSRs it
> doesn't need.
>
> 8183a538cd95 ("KVM: x86/pmu: Add IA32_DS_AREA MSR emulation to support guest DS")
> 902caeb6841a ("KVM: x86/pmu: Add PEBS_DATA_CFG MSR emulation to support adaptive PEBS")
> c59a1f106f5c ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")

These are 'Fixes:' tags I suppose?

...

--
Vitaly