Re: [PATCH v1 2/2] virtio-net: virtio_net_flush_tx() check for per-queue reset

[Xuan Zhuo]

On Sun, 29 Jan 2023 14:23:21 +0800, Jason Wang <jasowang@redhat.com> wrote:
> On Sun, Jan 29, 2023 at 10:52 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> >
> > Check whether it is per-queue reset state in virtio_net_flush_tx().
> >
> > Before per-queue reset, we need to recover async tx resources. At this
> > time, virtio_net_flush_tx() is called, but we should not try to send
> > new packets, so virtio_net_flush_tx() should check the current
> > per-queue reset state.
> >
> > Fixes: 7dc6be52 ("virtio-net: support queue reset")
> > Fixes: https://gitlab.com/qemu-project/qemu/-/issues/1451
> > Reported-by: Alexander Bulekov <alxndr@bu.edu>
> > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> > ---
> >  hw/net/virtio-net.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> > index 3ae909041a..fba6451a50 100644
> > --- a/hw/net/virtio-net.c
> > +++ b/hw/net/virtio-net.c
> > @@ -2627,7 +2627,8 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
> >      VirtQueueElement *elem;
> >      int32_t num_packets = 0;
> >      int queue_index = vq2q(virtio_get_queue_index(q->tx_vq));
> > -    if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > +    if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) ||
> > +        virtio_queue_reset_state(q->tx_vq)) {
>
> We have other places that check DRIVER_OK do we need to check queue
> reset as well?

I checked it again. I still think that the location of other checking DRIVER_OK
does not need to check the queue reset.

Thanks.


>
> E.g:
> virtio_net_can_receive()
> virtio_net_tx_{timer|bh}()
>
> Thanks
>
> >          return num_packets;
> >      }
> >
> > --
> > 2.32.0.3.g01195cf9f
> >
>