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Subject: Re: [PATCH] KVM: x86: reinstate vendor-agnostic check on SPEC_CTRL
 cpuid bits
To:     Sean Christopherson <seanjc@google.com>
Cc:     linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        stable@vger.kernel.org, "Denis V . Lunev" <den@openvz.org>
References: <20201203151516.14441-1-pbonzini@redhat.com>
 <X8pt5WxwJ+yOZUAq@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <b117165b-2ae5-e197-8f91-8827d1e0ceb9@redhat.com>
Date:   Sun, 6 Dec 2020 11:16:14 +0100
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On 04/12/20 18:12, Sean Christopherson wrote:
> Assuming that's
> the case, adding helpers in cpuid.h to detect guest support for SPEC_CTRL (and
> maybe for PRED_CMD?) would be helpful.  It'd reduce duplicate code and document
> that KVM allows cross-vendor emulation.  The condition for SPEC_CTRL support is
> especially long.

That's a great idea nevertheless.

Paolo