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Date:   Wed, 24 Aug 2022 19:13:50 +0200
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Subject: Re: [PATCH] KVM: x86: Expose Predictive Store Forwarding Disable
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To:     Jim Mattson <jmattson@google.com>, Babu Moger <babu.moger@amd.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org,
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        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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 <CALMp9eSKcwChbc=cgYpdrTCtt49S1uuRdYoe83yph3tXGN6a2Q@mail.gmail.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
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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.

Paolo