virtio_net: Fix not restoring real_num_rx_queues

[ Upstream commit 188313c137c4f76afd0862f50dbc185b198b9e2a ]

When _virtnet_set_queues() failed we did not restore real_num_rx_queues.
Fix this by placing the change of real_num_rx_queues after
_virtnet_set_queues().
This order is also in line with virtnet_set_channels().

Fixes: 4941d472 ("virtio-net: do not reset during XDP set")
Signed-off-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: NJason Wang <jasowang@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/virtio_net.c

@@ -2377,10 +2377,10 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
 		}
 	}
 
-	netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
 	err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
 	if (err)
 		goto err;
+	netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
 	vi->xdp_queue_pairs = xdp_qp;
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {