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From:   Jim Mattson <jmattson@google.com>
Date:   Wed, 24 Aug 2022 10:16:42 -0700
Message-ID: <CALMp9eQCcy-MjB8Su+654XyL3zfR876tdh4QHUjvB7EiNjCU9A@mail.gmail.com>
Subject: Re: [PATCH] KVM: x86: Expose Predictive Store Forwarding Disable
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Babu Moger <babu.moger@amd.com>, tglx@linutronix.de,
        mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com,
        seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com,
        joro@8bytes.org, tony.luck@intel.com, peterz@infradead.org,
        kyung.min.park@intel.com, wei.huang2@amd.com, jgross@suse.com,
        andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
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On Wed, Aug 24, 2022 at 10:13 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 8/23/22 23:26, Jim Mattson wrote:
> > For consistency, should this feature be renamed AMD_PSFD, now that
> > Intel is enumerating PSFD with CPUID.(EAX=7,ECX=2):EDX.PSFD[bit 0]?
> > Seehttps://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/cpuid-enumeration-and-architectural-msrs.html.
> >
> > And, Paolo, why are we carrying X86_FEATURE_PSFD as a private #define
> > in KVM rather than putting it where it belongs in cpufeatures.h?
> >
>
> 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?