net/mlx5e: TC, Don't offload CT commit if it's the last action

JIRA: https://issues.redhat.com/browse/RHEL-72226
JIRA: https://issues.redhat.com/browse/RHEL-73517
Upstream-status: v6.15-rc1

commit 56617e1
Author: Jianbo Liu <jianbol@nvidia.com>
Date:   Wed Mar 19 16:03:03 2025 +0200

    net/mlx5e: TC, Don't offload CT commit if it's the last action

    For CT action with commit argument, it's usually followed by the
    forward action, either to the output netdev or next chain. The default
    behavior for software is to drop by setting action attribute to
    TC_ACT_SHOT instead of TC_ACT_PIPE if it's the last action. But driver
    can't handle it, so block the offload for such case.

    Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
    Reviewed-by: Roi Dayan <roid@nvidia.com>
    Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
    Link: https://patch.msgid.link/1742392983-153050-6-git-send-email-tariqt@nvidia.com
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Benjamin Poirier <bpoirier@redhat.com>

Author: Benjamin Poirier

drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/ct.c

@@ -5,6 +5,16 @@
 #include "en/tc_priv.h"
 #include "en/tc_ct.h"
 
+static bool
+tc_act_can_offload_ct(struct mlx5e_tc_act_parse_state *parse_state,
+		      const struct flow_action_entry *act,
+		      int act_index,
+		      struct mlx5_flow_attr *attr)
+{
+	return !((act->ct.action & TCA_CT_ACT_COMMIT) &&
+		 flow_action_is_last_entry(parse_state->flow_action, act));
+}
+
 static int
 tc_act_parse_ct(struct mlx5e_tc_act_parse_state *parse_state,
 		const struct flow_action_entry *act,
@@ -56,6 +66,7 @@ tc_act_is_missable_ct(const struct flow_action_entry *act)
 }
 
 struct mlx5e_tc_act mlx5e_tc_act_ct = {
+	.can_offload = tc_act_can_offload_ct,
 	.parse_action = tc_act_parse_ct,
 	.post_parse = tc_act_post_parse_ct,
 	.is_multi_table_act = tc_act_is_multi_table_act_ct,