RDMA/mlx5: Check RoCE LAG status before getting netdev

Check if RoCE LAG is active before calling the LAG layer for netdev.
This clarifies if LAG is active. No behavior changes with this patch.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/20240909173025.30422-2-michaelgur@nvidia.com
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/hw/mlx5/main.c

@@ -198,12 +198,18 @@ static int mlx5_netdev_event(struct notifier_block *this,
 	case NETDEV_CHANGE:
 	case NETDEV_UP:
 	case NETDEV_DOWN: {
-		struct net_device *lag_ndev = mlx5_lag_get_roce_netdev(mdev);
 		struct net_device *upper = NULL;
 
-		if (lag_ndev) {
-			upper = netdev_master_upper_dev_get(lag_ndev);
-			dev_put(lag_ndev);
+		if (mlx5_lag_is_roce(mdev)) {
+			struct net_device *lag_ndev;
+
+			lag_ndev = mlx5_lag_get_roce_netdev(mdev);
+			if (lag_ndev) {
+				upper = netdev_master_upper_dev_get(lag_ndev);
+				dev_put(lag_ndev);
+			} else {
+				goto done;
+			}
 		}
 
 		if (ibdev->is_rep)
@@ -257,9 +263,10 @@ static struct net_device *mlx5_ib_get_netdev(struct ib_device *device,
 	if (!mdev)
 		return NULL;
 
-	ndev = mlx5_lag_get_roce_netdev(mdev);
-	if (ndev)
+	if (mlx5_lag_is_roce(mdev)) {
+		ndev = mlx5_lag_get_roce_netdev(mdev);
 		goto out;
+	}
 
 	/* Ensure ndev does not disappear before we invoke dev_hold()
 	 */