linux-kernel - Re: [PATCH 4/5] KVM: x86/mmu: Don't install TDP MMU SPTE if SP has unexpected level

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CALzav=d-9G6SSBCB=TbVWi9Szprm1wD3AqqgZzoCq26_LF_ySw@mail.gmail.com>
Date:   Tue, 13 Dec 2022 09:59:37 -0800
From:   David Matlack <dmatlack@...gle.com>
To:     Sean Christopherson <seanjc@...gle.com>
Cc:     Paolo Bonzini <pbonzini@...hat.com>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Robert Hoo <robert.hu@...ux.intel.com>,
        Greg Thelen <gthelen@...gle.com>,
        Ben Gardon <bgardon@...gle.com>,
        Mingwei Zhang <mizhang@...gle.com>
Subject: Re: [PATCH 4/5] KVM: x86/mmu: Don't install TDP MMU SPTE if SP has
 unexpected level

On Mon, Dec 12, 2022 at 7:30 PM Sean Christopherson <seanjc@...gle.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()?