virtio-net: fix recursived rtnl_lock() during probe()

The deadlock appears in a stack trace like:

  virtnet_probe()
    rtnl_lock()
    virtio_config_changed_work()
      netdev_notify_peers()
        rtnl_lock()

It happens if the VMM sends a VIRTIO_NET_S_ANNOUNCE request while the
virtio-net driver is still probing.

The config_work in probe() will get scheduled until virtnet_open() enables
the config change notification via virtio_config_driver_enable().

Fixes: df28de7 ("virtio-net: synchronize operstate with admin state on up/down")
Signed-off-by: Zigit Zo <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Acked-by: Jason Wang <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: plxty

drivers/net/virtio_net.c

@@ -7059,7 +7059,7 @@ static int virtnet_probe(struct virtio_device *vdev)
 	   otherwise get link status from config. */
 	netif_carrier_off(dev);
 	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
-		virtnet_config_changed_work(&vi->config_work);
+		virtio_config_changed(vi->vdev);
 	} else {
 		vi->status = VIRTIO_NET_S_LINK_UP;
 		virtnet_update_settings(vi);