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References: <20221213033030.83345-1-seanjc@google.com> <20221213033030.83345-5-seanjc@google.com>
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From:   David Matlack <dmatlack@google.com>
Date:   Tue, 13 Dec 2022 09:59:37 -0800
Message-ID: <CALzav=d-9G6SSBCB=TbVWi9Szprm1wD3AqqgZzoCq26_LF_ySw@mail.gmail.com>
Subject: Re: [PATCH 4/5] KVM: x86/mmu: Don't install TDP MMU SPTE if SP has
 unexpected level
To:     Sean Christopherson <seanjc@google.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Robert Hoo <robert.hu@linux.intel.com>,
        Greg Thelen <gthelen@google.com>,
        Ben Gardon <bgardon@google.com>,
        Mingwei Zhang <mizhang@google.com>
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On Mon, Dec 12, 2022 at 7:30 PM Sean Christopherson <seanjc@google.com> wrote:
>
> Don't install a leaf TDP MMU SPTE if the parent page's level doesn't
> match the target level of the fault, and instead have the vCPU retry the
> faulting instruction after warning.  Continuing on is completely
> unnecessary as the absolute worst case scenario of retrying is DoSing
> the vCPU, whereas continuing on all but guarantees bigger explosions, e.g.

Would it make sense to kill the VM instead via KVM_BUG()?