Re: [PATCH] KVM: x86: Expose Predictive Store Forwarding Disable

[Paolo Bonzini]

On 8/24/22 19:16, Jim Mattson wrote:
> > Borislav asked to not show psfd in /proc/cpuinfo, because Linux had
> > decided not to control PSF separately; instead it just piggybacked
> > on SSBD which should disable PSF as well.  Honestly I disagree but
> > it's not my area of maintenance.
>
> Do we expose PSFD in KVM for the use of another popular guest OS?

Yes, that was the purpose of this patch and we expose it via 
MSR_IA32_SPEC_CTRL (the only validation that KVM does is in 
kvm_spec_ctrl_test_value(), so it does not need to know more about the 
specific bits).

Paolo