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Tsirkin" To: Greg KH Subject: Re: [PATCH 1/1] vhost: Protect the virtqueue from being cleared whilst still in use Message-ID: <20220308060210-mutt-send-email-mst@kernel.org> References: <20220307191757.3177139-1-lee.jones@linaro.org> MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Cc: syzbot+adc3cb32385586bec859@syzkaller.appspotmail.com, kvm@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, virtualization@lists.linux-foundation.org, Lee Jones X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Tue, Mar 08, 2022 at 09:57:57AM +0100, Greg KH wrote: > > > And what happens if the mutex is locked _RIGHT_ after you checked it? > > > You still have a race... > > > > No, we miss a warning that one time. Memory is still protected. > > Then don't warn on something that doesn't matter. This line can be > dropped as there's nothing anyone can do about it, right? I mean, the reason I wanted the warning is because there's a kernel bug, and it will break userspace. warning is just telling us this. is the bug reacheable from userspace? if we knew that we won't need the lock ... -- MST _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization