[PATCH 4.12 23/52] net/mlx5e: Check for qos capability in dcbnl_initialize

[Greg Kroah-Hartman]

4.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Huy Nguyen <huyn@xxxxxxxxxxxx>


[ Upstream commit 33c52b6718d2a6cb414440c98560818910d896dc ]

qos capability is the master capability bit that determines
if the DCBX is supported for the PCI function. If this bit is off,
driver cannot run any dcbx code.

Fixes: e207b7e99176 ("net/mlx5e: ConnectX-4 firmware support for DCBX")
Signed-off-by: Huy Nguyen <huyn@xxxxxxxxxxxx>
Reviewed-by: Parav Pandit <parav@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
@@ -754,6 +754,9 @@ void mlx5e_dcbnl_initialize(struct mlx5e
 {
 	struct mlx5e_dcbx *dcbx = &priv->dcbx;
 
+	if (!MLX5_CAP_GEN(priv->mdev, qos))
+		return;
+
 	if (MLX5_CAP_GEN(priv->mdev, dcbx))
 		mlx5e_dcbnl_query_dcbx_mode(priv, &dcbx->mode);