virtio-net: fix race between set queues and probe

A race were found where set_channels could be called after registering
but before virtnet_set_queues() in virtnet_probe(). Fixing this by
moving the virtnet_set_queues() before netdevice registering. While at
it, use _virtnet_set_queues() to avoid holding rtnl as the device is
not even registered at that time.

Cc: stable@vger.kernel.org
Fixes: a220871be66f ("virtio-net: correctly enable multiqueue")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230725072049.617289-1-jasowang@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 0db14f6..1270c8d 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -4219,6 +4219,8 @@ 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();
 
@@ -4257,8 +4259,6 @@ static int virtnet_probe(struct virtio_device *vdev)
                goto free_unregister_netdev;
        }
 
-       virtnet_set_queues(vi, vi->curr_queue_pairs);
-
        /* Assume link up if device can't report link status,
           otherwise get link status from config. */
        netif_carrier_off(dev);