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:

quoted

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 [off-list ref]
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 [off-list ref]
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