[dpdk-stable] patch 'net/mlx5: fix constant array size' has been queued to stable release 20.11.1

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 20.11.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 02/07/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/89e0cd5ca7baa647abacbc96093d04a7e52dafd5

Thanks.

Luca Boccassi

---
>From 89e0cd5ca7baa647abacbc96093d04a7e52dafd5 Mon Sep 17 00:00:00 2001
From: Tal Shnaiderman <talshn at nvidia.com>
Date: Mon, 28 Dec 2020 11:54:05 +0200
Subject: [PATCH] net/mlx5: fix constant array size

[ upstream commit 09a5e9777e7eb0179e0f9a3b6830c89702df0bd7 ]

Before this commit the PMD used:
   const int elt_n = 8
   const int *stack[elt_n];

In Windows clang compiler complains:
net/mlx5/mlx5_flow.c:215:19: error: variable length array folded
to constant array as an extension [-Werror,-Wgnu-folding-constant]

Fix it by using a constant macro definition instead of a variable:
   #define MLX5_RSS_EXP_ELT_N 8
   const int *stack[MLX5_RSS_EXP_ELT_N];

Fixes: c7870bfe09dc ("ethdev: move RSS expansion code to mlx5 driver")

Signed-off-by: Tal Shnaiderman <talshn at nvidia.com>
Signed-off-by: Ophir Munk <ophirmu at nvidia.com>
Acked-by: Matan Azrad <matan at nvidia.com>
---
 drivers/net/mlx5/mlx5_flow.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
index 52ade39a42..a4cf63b235 100644
--- a/drivers/net/mlx5/mlx5_flow.c
+++ b/drivers/net/mlx5/mlx5_flow.c
@@ -212,6 +212,8 @@ mlx5_flow_expand_rss_item_complete(const struct rte_flow_item *item)
 	return ret;
 }
 
+#define MLX5_RSS_EXP_ELT_N 8
+
 /**
  * Expand RSS flows into several possible flows according to the RSS hash
  * fields requested and the driver capabilities.
@@ -242,13 +244,12 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,
 		     const struct mlx5_flow_expand_node graph[],
 		     int graph_root_index)
 {
-	const int elt_n = 8;
 	const struct rte_flow_item *item;
 	const struct mlx5_flow_expand_node *node = &graph[graph_root_index];
 	const int *next_node;
-	const int *stack[elt_n];
+	const int *stack[MLX5_RSS_EXP_ELT_N];
 	int stack_pos = 0;
-	struct rte_flow_item flow_items[elt_n];
+	struct rte_flow_item flow_items[MLX5_RSS_EXP_ELT_N];
 	unsigned int i;
 	size_t lsize;
 	size_t user_pattern_size = 0;
@@ -261,10 +262,10 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,
 
 	memset(&missed_item, 0, sizeof(missed_item));
 	lsize = offsetof(struct mlx5_flow_expand_rss, entry) +
-		elt_n * sizeof(buf->entry[0]);
+		MLX5_RSS_EXP_ELT_N * sizeof(buf->entry[0]);
 	if (lsize <= size) {
 		buf->entry[0].priority = 0;
-		buf->entry[0].pattern = (void *)&buf->entry[elt_n];
+		buf->entry[0].pattern = (void *)&buf->entry[MLX5_RSS_EXP_ELT_N];
 		buf->entries = 0;
 		addr = buf->entry[0].pattern;
 	}
@@ -367,7 +368,7 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,
 		/* Go deeper. */
 		if (node->next) {
 			next_node = node->next;
-			if (stack_pos++ == elt_n) {
+			if (stack_pos++ == MLX5_RSS_EXP_ELT_N) {
 				rte_errno = E2BIG;
 				return -rte_errno;
 			}
-- 
2.29.2

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-02-05 11:18:32.671293426 +0000
+++ 0076-net-mlx5-fix-constant-array-size.patch	2021-02-05 11:18:28.866692254 +0000
@@ -1 +1 @@
-From 09a5e9777e7eb0179e0f9a3b6830c89702df0bd7 Mon Sep 17 00:00:00 2001
+From 89e0cd5ca7baa647abacbc96093d04a7e52dafd5 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 09a5e9777e7eb0179e0f9a3b6830c89702df0bd7 ]
+
@@ -19 +20,0 @@
-Cc: stable at dpdk.org
@@ -29 +30 @@
-index 82e24d7067..bf86aaaa39 100644
+index 52ade39a42..a4cf63b235 100644