Re: [PATCH] x86/entry/64: Disallow RDPID in paranoid entry if KVM is enabled

[Borislav Petkov]

On Fri, Aug 21, 2020 at 10:09:01AM +0200, Paolo Bonzini wrote:
> One more MSR *is* a big deal: KVM's vmentry+vmexit cost is around 1000
> cycles, adding 100 clock cycles for 2 WRMSRs is a 10% increase.

The kernel uses TSC_AUX so we can't reserve it to KVM either.

-- 
Regards/Gruss,
    Boris.

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