Commit 73e87246 authored Jul 25, 2023 by Jason Wang Committed by Greg Kroah-Hartman Aug 11, 2023

virtio-net: fix race between set queues and probe



commit 25266128fe16d5632d43ada34c847d7b8daba539 upstream.

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: a220871b ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 6db2a3c5

drivers/net/virtio_net.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -3265,6 +3265,8 @@ static int virtnet_probe(struct virtio_device *vdev)
		}
		}

		_virtnet_set_queues(vi, vi->curr_queue_pairs);

		/* serialize netdev register + virtio_device_ready() with ndo_open() */
		rtnl_lock();

		@@ -3285,8 +3287,6 @@ 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);