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Tsirkin" To: Sean Christopherson Cc: Sebastian Andrzej Siewior , Paolo Bonzini , Jason Wang , kvm@vger.kernel.org, virtualization@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/3] vhost_task: Fix a bug where KVM wakes an exited task Message-ID: <20250918120658-mutt-send-email-mst@kernel.org> References: <20250827194107.4142164-1-seanjc@google.com> <20250827201059.EmmdDFB_@linutronix.de> <20250918110828-mutt-send-email-mst@kernel.org> <20250918154826.oUc0cW0Y@linutronix.de> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 7_bKFjj51o1namvJOsEgzpbJK-0DQsdzH72cdQfZsZk_1758211692 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Sep 18, 2025 at 09:04:07AM -0700, Sean Christopherson wrote: > On Thu, Sep 18, 2025, Sebastian Andrzej Siewior wrote: > > On 2025-09-18 11:09:05 [-0400], Michael S. Tsirkin wrote: > > > So how about switching to this approach then? > > > Instead of piling up fixes like we seem to do now ... > > I don't have a strong preference for 6.17, beyond landing a fix of some kind. > I think there are three options for 6.17, in order of "least like to break > something": > > 1. Sebastian's get_task_struct() fix I am just a bit apprehensive that we don't create a situation where we leak the task struct somehow, given the limited testing time. Can you help me get convinced that risk is 0? > 2. This series, without the KILLED sanity check in __vhost_task_wake() > 3. This series, with my fixup (with which syzbot was happy) > > Longer term, I'd still like to land everything though. No problem with that. > > > Sean? > > > > Since I am in To: here. You want me to resent my diff as a proper patch? > > Ya, I think it makes sense to harden against UAF even if we fix the KVM bug more > directly.