Subject: [net 07/11] net/mlx5e: In skb build skip setting mark in switchdev mode

From: Saeed Mahameed <[email-masked]>
Date: Thu, 7 Jan 2021 12:28:41 -0800

From: Maor Dickman <[email-masked]>

sop_drop_qpn field in the cqe is used by two features, in SWITCHDEV mode
to restore the chain id in case of a miss and in LEGACY mode to support
skbedit mark action. In build RX skb, the skb mark field is set regardless
of the configured mode which cause a corruption of the mark field in case
of switchdev mode.

Fix by overriding the mark value back to 0 in the representor tc update
skb flow.

Fixes: 8f1e0b97cc70 ("net/mlx5: E-Switch, Mark miss packets with new chain id mapping")
Signed-off-by: Maor Dickman <[email-masked]>
Reviewed-by: Raed Salem <[email-masked]>
Reviewed-by: Oz Shlomo <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c
index d29af7b9c695..76177f7c5ec2 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c
@@ -626,6 +626,11 @@ bool mlx5e_rep_tc_update_skb(struct mlx5_cqe64 *cqe,
 	if (!reg_c0)
 		return true;
 
+	/* If reg_c0 is not equal to the default flow tag then skb->mark
+	 * is not supported and must be reset back to 0.
+	 */
+	skb->mark = 0;
+
 	priv = netdev_priv(skb->dev);
 	esw = priv->mdev->priv.eswitch;
 
-- 
2.26.2