[dpdk-stable] patch 'net: fix how L4 checksum choice is tested' has been queued to LTS release 18.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 08/28/19. 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/kevintraynor/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable-queue/commit/3ad4739521ccae17e04135938b55c27a4988faf0

Thanks.

Kevin Traynor

---
>From 3ad4739521ccae17e04135938b55c27a4988faf0 Mon Sep 17 00:00:00 2001
From: Ivan Malov <ivan.malov at oktetlabs.ru>
Date: Fri, 28 Jun 2019 06:13:09 +0300
Subject: [PATCH] net: fix how L4 checksum choice is tested

[ upstream commit 39a94299195f3329a28a3556e2431b9d6b83b222 ]

The API to prepare checksum offloads mistreats L4
checksum type enum values as self-contained flags.

Turning these flag checks into enum checks causes
warnings by GCC about possibly uninitialised IPv4
header pointer. The issue was found to show up in
the case of GCC versions 4.8.5 and 5.4.0, however,
it might be the case for a wider variety of other
versions. Initialise the pointer upon declaration.
and explain the reason behind this in the comment.

Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")

Signed-off-by: Ivan Malov <ivan.malov at oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <arybchenko at solarflare.com>
Acked-by: Stephen Hemminger <stephen at networkplumber.org>
Acked-by: Konstantin Ananyev <konstantin.ananyev at intel.com>
---
 lib/librte_net/rte_net.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/librte_net/rte_net.h b/lib/librte_net/rte_net.h
index a8eafa146..025acba7f 100644
--- a/lib/librte_net/rte_net.h
+++ b/lib/librte_net/rte_net.h
@@ -113,5 +113,6 @@ static inline int
 rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 {
-	struct ipv4_hdr *ipv4_hdr;
+	/* Initialise ipv4_hdr to avoid false positive compiler warnings. */
+	struct ipv4_hdr *ipv4_hdr = NULL;
 	struct ipv6_hdr *ipv6_hdr;
 	struct tcp_hdr *tcp_hdr;
@@ -130,5 +131,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 	}
 
-	if ((ol_flags & PKT_TX_UDP_CKSUM) == PKT_TX_UDP_CKSUM) {
+	if ((ol_flags & PKT_TX_L4_MASK) == PKT_TX_UDP_CKSUM) {
 		if (ol_flags & PKT_TX_IPV4) {
 			udp_hdr = (struct udp_hdr *)((char *)ipv4_hdr +
@@ -145,5 +146,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 					ol_flags);
 		}
-	} else if ((ol_flags & PKT_TX_TCP_CKSUM) ||
+	} else if ((ol_flags & PKT_TX_L4_MASK) == PKT_TX_TCP_CKSUM ||
 			(ol_flags & PKT_TX_TCP_SEG)) {
 		if (ol_flags & PKT_TX_IPV4) {
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2019-08-22 19:38:22.094524402 +0100
+++ 0025-net-fix-how-L4-checksum-choice-is-tested.patch	2019-08-22 19:38:20.445026689 +0100
@@ -1 +1 @@
-From 39a94299195f3329a28a3556e2431b9d6b83b222 Mon Sep 17 00:00:00 2001
+From 3ad4739521ccae17e04135938b55c27a4988faf0 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 39a94299195f3329a28a3556e2431b9d6b83b222 ]
+
@@ -18 +19,0 @@
-Cc: stable at dpdk.org
@@ -29 +30 @@
-index 461f2c81d..1560ecfa4 100644
+index a8eafa146..025acba7f 100644
@@ -32 +33 @@
-@@ -114,5 +114,6 @@ static inline int
+@@ -113,5 +113,6 @@ static inline int
@@ -35 +36 @@
--	struct rte_ipv4_hdr *ipv4_hdr;
+-	struct ipv4_hdr *ipv4_hdr;
@@ -37,4 +38,4 @@
-+	struct rte_ipv4_hdr *ipv4_hdr = NULL;
- 	struct rte_ipv6_hdr *ipv6_hdr;
- 	struct rte_tcp_hdr *tcp_hdr;
-@@ -152,5 +153,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
++	struct ipv4_hdr *ipv4_hdr = NULL;
+ 	struct ipv6_hdr *ipv6_hdr;
+ 	struct tcp_hdr *tcp_hdr;
+@@ -130,5 +131,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
@@ -46,2 +47,2 @@
- 			udp_hdr = (struct rte_udp_hdr *)((char *)ipv4_hdr +
-@@ -168,5 +169,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
+ 			udp_hdr = (struct udp_hdr *)((char *)ipv4_hdr +
+@@ -145,5 +146,5 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)