Commit 0d5b7138 authored Aug 09, 2023 by Jason Wang Committed by sanglipeng Feb 23, 2024

virtio-net: set queues after driver_ok

stable inclusion
from stable-v5.10.192
commit 9aead733f5e0d40e3d2798f4d2fd4a5d7930111c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I933RF

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9aead733f5e0d40e3d2798f4d2fd4a5d7930111c



--------------------------------

commit 51b81317 upstream.

Commit 25266128 ("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: 25266128 ("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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>

parent a47141d3

drivers/net/virtio_net.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -3226,8 +3226,6 @@ 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();

		@@ -3240,6 +3238,8 @@ static int virtnet_probe(struct virtio_device *vdev)

		virtio_device_ready(vdev);

		_virtnet_set_queues(vi, vi->curr_queue_pairs);

		rtnl_unlock();

		err = virtnet_cpu_notif_add(vi);