[PATCH 4.4 215/312] net/mlx4_core: Check device state before unregistering it

[Greg Kroah-Hartman]

From: Alex Vesker <valex@xxxxxxxxxxxx>

commit 9b022a6e0f26af108b9105b16b310393c898d9bd upstream.

Verify that the device state is registered before un-registering it.
This check is required to prevent an OOPS on flows that do
re-registration of the device and its previous state was
unregistered.

Fixes: 225c7b1feef1 ("IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters")
Signed-off-by: Alex Vesker <valex@xxxxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/ethernet/mellanox/mlx4/intf.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx4/intf.c
+++ b/drivers/net/ethernet/mellanox/mlx4/intf.c
@@ -217,6 +217,9 @@ void mlx4_unregister_device(struct mlx4_
 	struct mlx4_priv *priv = mlx4_priv(dev);
 	struct mlx4_interface *intf;
 
+	if (!(dev->persist->interface_state & MLX4_INTERFACE_STATE_UP))
+		return;
+
 	mlx4_stop_catas_poll(dev);
 	if (dev->persist->interface_state & MLX4_INTERFACE_STATE_DELETION &&
 	    mlx4_is_slave(dev)) {