net/mlx4_en: Call register_netdevice in the proper location

commit e5eda89d upstream.

Netdevice registration should be performed a the end of the driver
initialization flow. If we don't do that, after calling register_netdevice,
device callbacks may be issued by higher layers of the stack before
final configuration of the device is done.

For example (VXLAN configuration race), mlx4_SET_PORT_VXLAN was issued
after the register_netdev command. System network scripts may configure
the interface (UP) right after the registration, which also attach
unicast VXLAN steering rule, before mlx4_SET_PORT_VXLAN was called,
causing the firmware to fail the rule attachment.

Fixes: 837052d0 ("net/mlx4_en: Add netdev support for TCP/IP offloads of vxlan tunneling")
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/net/ethernet/mellanox/mlx4/en_netdev.c

@@ -2619,13 +2619,6 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
 	netif_carrier_off(dev);
 	mlx4_en_set_default_moderation(priv);
 
-	err = register_netdev(dev);
-	if (err) {
-		en_err(priv, "Netdev registration failed for port %d\n", port);
-		goto out;
-	}
-	priv->registered = 1;
-
 	en_warn(priv, "Using %d TX rings\n", prof->tx_ring_num);
 	en_warn(priv, "Using %d RX rings\n", prof->rx_ring_num);
 
@@ -2665,6 +2658,14 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
 		queue_delayed_work(mdev->workqueue, &priv->service_task,
 				   SERVICE_TASK_DELAY);
 
+	err = register_netdev(dev);
+	if (err) {
+		en_err(priv, "Netdev registration failed for port %d\n", port);
+		goto out;
+	}
+
+	priv->registered = 1;
+
 	return 0;
 
 out: