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From:   Jim Mattson <jmattson@google.com>
Date:   Mon, 17 May 2021 14:09:47 -0700
Message-ID: <CALMp9eSR3tAZx3iW4_aVRWtFvVma-NYC979SDG5z3MG-F4M5dw@mail.gmail.com>
Subject: Re: [PATCH 1/2] KVM: x86: Invert APICv/AVIC enablement check
To:     Sean Christopherson <seanjc@google.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        kvm list <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Kechen Lu <kechenl@nvidia.com>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, May 17, 2021 at 2:03 PM Sean Christopherson <seanjc@google.com> wrote:
>
> On Thu, May 13, 2021, Vitaly Kuznetsov wrote:
> > Currently, APICv/AVIC enablement is global ('enable_apicv' module parameter
> > for Intel, 'avic' module parameter for AMD) but there's no way to check
> > it from vendor-neutral code. Add 'apicv_supported()' to kvm_x86_ops and
> > invert kvm_apicv_init() (which now doesn't need to be called from arch-
> > specific code).
>
> Rather than add a new hook, just move the variable to x86.c, and export it so
> that VMX and SVM can give it different module names.  The only hiccup is that
> avic is off by default, but I don't see why that can't be changed.

See https://www.spinics.net/lists/kvm/msg208722.html.