| Message ID | 20230810031256.813284-1-jasowang@redhat.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,V2] virtio-net: set queues after driver_ok | expand |
On Wed, 9 Aug 2023 23:12:56 -0400 Jason Wang wrote: > Commit 25266128fe16 ("virtio-net: fix race between set queues and > probe") tries to fix the race between set queues and probe by calling > _virtnet_set_queues() before DRIVER_OK is set. This violates virtio > spec. Fixing this by setting queues after virtio_device_ready(). > > Note that rtnl needs to be held for userspace requests to change the > number of queues. So we are serialized in this way. FTR this appears to have been applied yesterday by DaveM. Thanks!
On 10/8/2023 11:12 am, Jason Wang wrote: > Commit 25266128fe16 ("virtio-net: fix race between set queues and > probe") tries to fix the race between set queues and probe by calling > _virtnet_set_queues() before DRIVER_OK is set. This violates virtio > spec. Fixing this by setting queues after virtio_device_ready(). > > Note that rtnl needs to be held for userspace requests to change the > number of queues. So we are serialized in this way. > > Fixes: 25266128fe16 ("virtio-net: fix race between set queues and probe") > Reported-by: Dragos Tatulea <dtatulea@nvidia.com> I had the same issue to report and this fix helped me out. Tested-by: Like Xu <likexu@tencent.com> > Acked-by: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > The patch is needed for -stable. > Changes since V1: Tweak the commit log. > --- > drivers/net/virtio_net.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 1270c8d23463..ff03921e46df 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -4219,8 +4219,6 @@ static int virtnet_probe(struct virtio_device *vdev) > if (vi->has_rss || vi->has_rss_hash_report) > virtnet_init_default_rss(vi); > > - _virtnet_set_queues(vi, vi->curr_queue_pairs); > - > /* serialize netdev register + virtio_device_ready() with ndo_open() */ > rtnl_lock(); > > @@ -4233,6 +4231,8 @@ static int virtnet_probe(struct virtio_device *vdev) > > virtio_device_ready(vdev); > > + _virtnet_set_queues(vi, vi->curr_queue_pairs); > + > /* a random MAC address has been assigned, notify the device. > * We don't fail probe if VIRTIO_NET_F_CTRL_MAC_ADDR is not there > * because many devices work fine without getting MAC explicitly
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 1270c8d23463..ff03921e46df 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -4219,8 +4219,6 @@ static int virtnet_probe(struct virtio_device *vdev) if (vi->has_rss || vi->has_rss_hash_report) virtnet_init_default_rss(vi); - _virtnet_set_queues(vi, vi->curr_queue_pairs); - /* serialize netdev register + virtio_device_ready() with ndo_open() */ rtnl_lock(); @@ -4233,6 +4231,8 @@ static int virtnet_probe(struct virtio_device *vdev) virtio_device_ready(vdev); + _virtnet_set_queues(vi, vi->curr_queue_pairs); + /* a random MAC address has been assigned, notify the device. * We don't fail probe if VIRTIO_NET_F_CTRL_MAC_ADDR is not there * because many devices work fine without getting MAC explicitly
Commit 25266128fe16 ("virtio-net: fix race between set queues and probe") tries to fix the race between set queues and probe by calling _virtnet_set_queues() before DRIVER_OK is set. This violates virtio spec. Fixing this by setting queues after virtio_device_ready(). Note that rtnl needs to be held for userspace requests to change the number of queues. So we are serialized in this way. Fixes: 25266128fe16 ("virtio-net: fix race between set queues and probe") Reported-by: Dragos Tatulea <dtatulea@nvidia.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- The patch is needed for -stable. Changes since V1: Tweak the commit log. --- drivers/net/virtio_net.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)