Subject: [net 12/16] net/mlx5e: Fix error path of updating netdev queues

From: Saeed Mahameed <[email-masked]>
Date: Tue, 18 May 2021 23:05:19 -0700

From: Aya Levin <[email-masked]>

Avoid division by zero in the error flow. In the driver TC number can be
either 1 or 8. When TC count is set to 1, driver zero netdev->num_tc.
Hence, need to convert it back from 0 to 1 in the error flow.

Fixes: fa3748775b92 ("net/mlx5e: Handle errors from netif_set_real_num_{tx,rx}_queues")
Signed-off-by: Aya Levin <[email-masked]>
Reviewed-by: Maxim Mikityanskiy <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 89937b055070..d1b9a4040d60 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -2697,7 +2697,7 @@ static int mlx5e_update_netdev_queues(struct mlx5e_priv *priv)
 	int err;
 
 	old_num_txqs = netdev->real_num_tx_queues;
-	old_ntc = netdev->num_tc;
+	old_ntc = netdev->num_tc ? : 1;
 
 	nch = priv->channels.params.num_channels;
 	ntc = priv->channels.params.num_tc;
-- 
2.31.1