[PATCH 5.10 046/103] net/mlx5e: In skb build skip setting mark in switchdev mode

From: Greg Kroah-Hartman
Date: Fri Jan 15 2021 - 07:46:05 EST


From: Maor Dickman <maord@xxxxxxxxxx>

[ Upstream commit e13ed0ac064dd6ee964155ba9fdc2f3c3785934c ]

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 <maord@xxxxxxxxxx>
Reviewed-by: Raed Salem <raeds@xxxxxxxxxx>
Reviewed-by: Oz Shlomo <ozsh@xxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c | 5 +++++
1 file changed, 5 insertions(+)

--- 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
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;