[dpdk-stable] patch 'net/mlx5: fix redundant flow after RSS expansion' has been queued to stable release 20.11.2

[Xueming Li]

Hi,

FYI, your patch has been queued to stable release 20.11.2

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 05/12/21. 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/steevenlee/dpdk

This queued commit can be viewed at:
https://github.com/steevenlee/dpdk/commit/fb455a8129a59c07719a6092aaaa96bfd310fadc

Thanks.

Xueming Li <xuemingl at nvidia.com>

---
>From fb455a8129a59c07719a6092aaaa96bfd310fadc Mon Sep 17 00:00:00 2001
From: Xiaoyu Min <jackmin at nvidia.com>
Date: Tue, 30 Mar 2021 21:40:32 +0800
Subject: [PATCH] net/mlx5: fix redundant flow after RSS expansion
Cc: Luca Boccassi <bluca at debian.org>

[ upstream commit c1d397a67eed3b9d7adce5e73c5352de040b3b65 ]

When RSS expand, if there is no expansion happened but completion
happened because user only input next protocol field instead of item
i.e, ether type == 0x8100 instead of VLAN, an extra flow is created with
missing item in order to filter traffic strictly.

However, after [1] and [2] the rte_flow_item_eth itself is enough to
filter out VLAN traffic, the VLAN item is not needed.

[1]: commit 09315fc83861 ("ethdev: add VLAN attributes to ethernet and VLAN items")
[2]: commit 86b59a1af671 ("net/mlx5: support VLAN matching fields")

This redundant flow will cause failure in some scenarios on group 0 due
to they are the same FTE.

Fixes: fc2dd8dd492f ("ethdev: fix expand RSS flows")

Signed-off-by: Xiaoyu Min <jackmin at nvidia.com>
Acked-by: Matan Azrad <matan at nvidia.com>
---
 drivers/net/mlx5/mlx5_flow.c | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
index 2fe810c6b5..5c2712329b 100644
--- a/drivers/net/mlx5/mlx5_flow.c
+++ b/drivers/net/mlx5/mlx5_flow.c
@@ -385,22 +385,6 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,
 		}
 		node = *next_node ? &graph[*next_node] : NULL;
 	};
-	/* no expanded flows but we have missed item, create one rule for it */
-	if (buf->entries == 1 && missed != 0) {
-		elt = 2;
-		lsize += elt * sizeof(*item) + user_pattern_size;
-		if (lsize <= size) {
-			buf->entry[buf->entries].priority = 1;
-			buf->entry[buf->entries].pattern = addr;
-			buf->entries++;
-			flow_items[0].type = missed_item.type;
-			flow_items[1].type = RTE_FLOW_ITEM_TYPE_END;
-			rte_memcpy(addr, buf->entry[0].pattern,
-				   user_pattern_size);
-			addr = (void *)(((uintptr_t)addr) + user_pattern_size);
-			rte_memcpy(addr, flow_items, elt * sizeof(*item));
-		}
-	}
 	return lsize;
 }
 
-- 
2.25.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-05-10 23:59:31.366052200 +0800
+++ 0186-net-mlx5-fix-redundant-flow-after-RSS-expansion.patch	2021-05-10 23:59:26.630000000 +0800
@@ -1 +1 @@
-From c1d397a67eed3b9d7adce5e73c5352de040b3b65 Mon Sep 17 00:00:00 2001
+From fb455a8129a59c07719a6092aaaa96bfd310fadc Mon Sep 17 00:00:00 2001
@@ -4,0 +5,3 @@
+Cc: Luca Boccassi <bluca at debian.org>
+
+[ upstream commit c1d397a67eed3b9d7adce5e73c5352de040b3b65 ]
@@ -21 +23,0 @@
-Cc: stable at dpdk.org
@@ -30 +32 @@
-index 0f1a9c5ed9..b34d2952b1 100644
+index 2fe810c6b5..5c2712329b 100644
@@ -33 +35 @@
-@@ -384,22 +384,6 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,
+@@ -385,22 +385,6 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size,