[3.16.y-ckt stable] Patch "net/mlx4_en: Call register_netdevice in the proper location" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    net/mlx4_en: Call register_netdevice in the proper location

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 35dd2e411a7c6f85e8c0eed9409a326125e40a4c Mon Sep 17 00:00:00 2001
From: Ido Shamay <idos at mellanox.com>
Date: Tue, 24 Mar 2015 15:18:38 +0200
Subject: net/mlx4_en: Call register_netdevice in the proper location

commit e5eda89d97ec256ba14e7e861387cc0468259c18 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: 837052d0ccc5 ("net/mlx4_en: Add netdev support for TCP/IP offloads of vxlan tunneling")
Signed-off-by: Ido Shamay <idos at mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz at mellanox.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 04b2d8e117cb..1b67e902aee6 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/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: