[dpdk-dev] [PATCH] net/mlx5: fix default RSS level

[Shahaf Shuler]

Using inner RSS by default for GRE leads to memory corruption as the
extra flow items added for the inner RSS are not counted in the flow
attributes buffer size.

Fixing by enforcing the default RSS level to be outer. This much
simplify the flow engine and more robust.
Future optimization for out of the box RSS can be done on subsequent
commits.

Fixes: d4a405186b73 ("net/mlx5: support tunnel RSS level")
Cc: xuemingl at mellanox.com
Cc: matan at mellanox.com

Signed-off-by: Shahaf Shuler <shahafs at mellanox.com>
---
 drivers/net/mlx5/mlx5_flow.c | 22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
index 0c0d6f99ad..994be05be6 100644
--- a/drivers/net/mlx5/mlx5_flow.c
+++ b/drivers/net/mlx5/mlx5_flow.c
@@ -805,7 +805,7 @@ mlx5_flow_convert_actions(struct rte_eth_dev *dev,
 			}
 			parser->rss_conf = (struct rte_flow_action_rss){
 				.func = RTE_ETH_HASH_FUNCTION_DEFAULT,
-				.level = rss->level,
+				.level = rss->level ? rss->level : 1,
 				.types = rss->types,
 				.key_len = rss_key_len,
 				.queue_num = rss->queue_num,
@@ -1166,9 +1166,6 @@ mlx5_flow_convert_rss(struct mlx5_flow_parse *parser)
 	int outer = parser->tunnel && parser->rss_conf.level < 2;
 	uint64_t rss = parser->rss_conf.types;
 
-	/* Default to outer RSS. */
-	if (!parser->rss_conf.level)
-		parser->rss_conf.level = 1;
 	layer = outer ? parser->out_layer : parser->layer;
 	if (layer == HASH_RXQ_TUNNEL)
 		layer = HASH_RXQ_ETH;
@@ -1801,9 +1798,6 @@ mlx5_flow_create_vxlan(const struct rte_flow_item *item,
 	parser->tunnel = ptype_ext[PTYPE_IDX(RTE_PTYPE_TUNNEL_VXLAN)];
 	parser->out_layer = parser->layer;
 	parser->layer = HASH_RXQ_TUNNEL;
-	/* Default VXLAN to outer RSS. */
-	if (!parser->rss_conf.level)
-		parser->rss_conf.level = 1;
 	if (spec) {
 		if (!mask)
 			mask = default_mask;
@@ -1876,9 +1870,6 @@ mlx5_flow_create_vxlan_gpe(const struct rte_flow_item *item,
 	parser->tunnel = ptype_ext[PTYPE_IDX(RTE_PTYPE_TUNNEL_VXLAN_GPE)];
 	parser->out_layer = parser->layer;
 	parser->layer = HASH_RXQ_TUNNEL;
-	/* Default VXLAN-GPE to outer RSS. */
-	if (!parser->rss_conf.level)
-		parser->rss_conf.level = 1;
 	if (spec) {
 		if (!mask)
 			mask = default_mask;
@@ -1956,9 +1947,6 @@ mlx5_flow_create_gre(const struct rte_flow_item *item,
 	parser->tunnel = ptype_ext[PTYPE_IDX(RTE_PTYPE_TUNNEL_GRE)];
 	parser->out_layer = parser->layer;
 	parser->layer = HASH_RXQ_TUNNEL;
-	/* Default GRE to inner RSS. */
-	if (!parser->rss_conf.level)
-		parser->rss_conf.level = 2;
 #ifdef HAVE_IBV_DEVICE_MPLS_SUPPORT
 	if (spec) {
 		if (!mask)
@@ -2052,12 +2040,6 @@ mlx5_flow_create_mpls(const struct rte_flow_item *item,
 		/* parser->out_layer stays as in GRE out_layer. */
 	}
 	parser->layer = HASH_RXQ_TUNNEL;
-	/*
-	 * For MPLS-in-GRE, RSS level should have been set.
-	 * For MPLS-in-UDP, use outer RSS.
-	 */
-	if (!parser->rss_conf.level)
-		parser->rss_conf.level = 1;
 	if (spec) {
 		if (!mask)
 			mask = default_mask;
@@ -2501,7 +2483,7 @@ mlx5_flow_list_create(struct rte_eth_dev *dev,
 	flow->tunnel = parser.tunnel;
 	flow->rss_conf = (struct rte_flow_action_rss){
 		.func = RTE_ETH_HASH_FUNCTION_DEFAULT,
-		.level = 0,
+		.level = parser.rss_conf.level,
 		.types = parser.rss_conf.types,
 		.key_len = parser.rss_conf.key_len,
 		.queue_num = parser.rss_conf.queue_num,
-- 
2.12.0