[dpdk-stable] [PATCH v1] ethdev:: fix redundant flow after RSS expansion

[dpdk-stable] [PATCH v1] ethdev:: fix redundant flow after RSS expansion

[Lior Margalit]

[ 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: 4ed05fcd441b ("ethdev: add flow API to expand RSS flows")
Cc: stable@dpdk.org

Signed-off-by: Lior Margalit <lmargalit@nvidia.com>
---
 lib/librte_ethdev/rte_flow.c | 18 ------------------
 1 file changed, 18 deletions(-)

diff --git a/lib/librte_ethdev/rte_flow.c b/lib/librte_ethdev/rte_flow.c
index 9964a241c..cf0b46780 100644
--- a/lib/librte_ethdev/rte_flow.c
+++ b/lib/librte_ethdev/rte_flow.c
@@ -1204,23 +1204,5 @@ rte_flow_expand_rss(struct rte_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));
-			addr = (void *)(((uintptr_t)addr) +
-					elt * sizeof(*item));
-		}
-	}
 	return lsize;
 }
-- 
2.25.1