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Date:   Thu, 28 Sep 2023 17:42:20 -0700
In-Reply-To: <20230928173354.217464-3-mlevitsk@redhat.com>
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Subject: Re: [PATCH v2 2/4] x86: KVM: SVM: add support for Invalid IPI Vector interception
From:   Sean Christopherson <seanjc@google.com>
To:     Maxim Levitsky <mlevitsk@redhat.com>
Cc:     kvm@vger.kernel.org, iommu@lists.linux.dev,
        "H. Peter Anvin" <hpa@zytor.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>, Joerg Roedel <joro@8bytes.org>,
        x86@kernel.org,
        Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
        linux-kernel@vger.kernel.org,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Will Deacon <will@kernel.org>, Ingo Molnar <mingo@redhat.com>,
        Robin Murphy <robin.murphy@arm.com>, stable@vger.kernel.org
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On Thu, Sep 28, 2023, Maxim Levitsky wrote:
> In later revisions of AMD's APM, there is a new 'incomplete IPI' exit code:
> 
> "Invalid IPI Vector - The vector for the specified IPI was set to an
> illegal value (VEC < 16)"
> 
> Note that tests on Zen2 machine show that this VM exit doesn't happen and
> instead AVIC just does nothing.
> 
> Add support for this exit code by doing nothing, instead of filling
> the kernel log with errors.
> 
> Also replace an unthrottled 'pr_err()' if another unknown incomplete
> IPI exit happens with vcpu_unimpl()
> 
> (e.g in case AMD adds yet another 'Invalid IPI' exit reason)
> 
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> ---

Reviewed-by: Sean Christopherson <seanjc@google.com>