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Tsirkin" To: Will Deacon Cc: syzbot , davem@davemloft.net, edumazet@google.com, eperezma@redhat.com, horms@kernel.org, jasowang@redhat.com, kuba@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, sgarzare@redhat.com, stefanha@redhat.com, syzkaller-bugs@googlegroups.com, virtualization@lists.linux.dev, xuanzhuo@linux.alibaba.com Subject: Re: [syzbot] [kvm?] [net?] [virt?] WARNING in virtio_transport_send_pkt_info Message-ID: <20250815063140-mutt-send-email-mst@kernel.org> References: <20250812052645-mutt-send-email-mst@kernel.org> <689b1156.050a0220.7f033.011c.GAE@google.com> <20250812061425-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Aug 15, 2025 at 11:09:24AM +0100, Will Deacon wrote: > On Tue, Aug 12, 2025 at 06:15:46AM -0400, Michael S. Tsirkin wrote: > > On Tue, Aug 12, 2025 at 03:03:02AM -0700, syzbot wrote: > > > Hello, > > > > > > syzbot has tested the proposed patch but the reproducer is still triggering an issue: > > > WARNING in virtio_transport_send_pkt_info > > > > OK so the issue triggers on > > commit 6693731487a8145a9b039bc983d77edc47693855 > > Author: Will Deacon > > Date: Thu Jul 17 10:01:16 2025 +0100 > > > > vsock/virtio: Allocate nonlinear SKBs for handling large transmit buffers > > > > > > but does not trigger on: > > > > commit 8ca76151d2c8219edea82f1925a2a25907ff6a9d > > Author: Will Deacon > > Date: Thu Jul 17 10:01:15 2025 +0100 > > > > vsock/virtio: Rename virtio_vsock_skb_rx_put() > > > > > > > > Will, I suspect your patch merely uncovers a latent bug > > in zero copy handling elsewhere. > > Want to take a look? > > Sorry for the delay, I was debugging something else! > > I see Hillf already tried some stuff in the other thread, but I can take > a look as well. > > Will I will be frank I don't understand how that patch makes sense though. -- MST