[PATCH] net/mlx5: fix error notification for large patterns

[PATCH] net/mlx5: fix error notification for large patterns

[Gregory Etelson]

HWS has limited resources to translate flow pattern.
When pattern translation does not fit STE, HWS translation fails with
E2BIG error.

The patch verifies that the E2BIG error value is kept during flow
error notification.

Fixes: e38776c36c8a ("net/mlx5: introduce HWS for non-template flow API")
Signed-off-by: Gregory Etelson <getelson@nvidia.com>
Acked-by: Dariusz Sosnowski <dsosnowski@nvidia.com>
---
 drivers/net/mlx5/hws/mlx5dr_bwc.c | 2 +-
 drivers/net/mlx5/mlx5_flow_hw.c   | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/mlx5/hws/mlx5dr_bwc.c b/drivers/net/mlx5/hws/mlx5dr_bwc.c
index 9233452118..0086cd2c90 100644
--- a/drivers/net/mlx5/hws/mlx5dr_bwc.c
+++ b/drivers/net/mlx5/hws/mlx5dr_bwc.c
@@ -137,7 +137,7 @@ mlx5dr_bwc_matcher_create(struct mlx5dr_table *table,
 						     bwc_matcher->num_of_at,
 						     &attr);
 	if (!bwc_matcher->matcher) {
-		rte_errno = EINVAL;
+		/* rte_errno must be set */
 		goto free_at;
 	}
 
diff --git a/drivers/net/mlx5/mlx5_flow_hw.c b/drivers/net/mlx5/mlx5_flow_hw.c
index 20d38ce414..b79e629d52 100644
--- a/drivers/net/mlx5/mlx5_flow_hw.c
+++ b/drivers/net/mlx5/mlx5_flow_hw.c
@@ -13894,7 +13894,7 @@ static int flow_hw_register_matcher(struct rte_eth_dev *dev,
 		if (sub_error.type != RTE_FLOW_ERROR_TYPE_NONE)
 			rte_memcpy(error, &sub_error, sizeof(sub_error));
 	}
-	return rte_flow_error_set(error, ENOMEM,
+	return rte_flow_error_set(error, rte_errno,
 					RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
 					NULL, "fail to register matcher");
 }
@@ -14070,8 +14070,12 @@ flow_hw_create_flow(struct rte_eth_dev *dev, enum mlx5_flow_type type,
 			goto error;
 		}
 	ret = flow_hw_register_matcher(dev, attr, items, external, *flow, &matcher, error);
-	if (ret)
+	if (ret) {
+		if (rte_errno == E2BIG)
+			rte_flow_error_set(error, E2BIG, RTE_FLOW_ERROR_TYPE_ITEM, NULL,
+				"flow pattern is too big");
 		goto error;
+	}
 
 	/*
 	 * ASO allocation – iterating on actions list to allocate missing resources.
-- 
2.48.1

Re: [PATCH] net/mlx5: fix error notification for large patterns

[Raslan Darawsheh]

Hi,


On 06/05/2025 4:31 PM, Gregory Etelson wrote:
> HWS has limited resources to translate flow pattern.
> When pattern translation does not fit STE, HWS translation fails with
> E2BIG error.
> 
> The patch verifies that the E2BIG error value is kept during flow
> error notification.
> 
> Fixes: e38776c36c8a ("net/mlx5: introduce HWS for non-template flow API")
> Signed-off-by: Gregory Etelson <getelson@nvidia.com>
> Acked-by: Dariusz Sosnowski <dsosnowski@nvidia.com>


Patch applied to next-net-mlx,

-- 
Kindest regards
Raslan Darawsheh