[dpdk-stable] patch 'net/enic: fix TSO for packets greater than 9208 bytes' has been queued to stable release 17.08.1

[Yuanhan Liu]

Hi,

FYI, your patch has been queued to stable release 17.08.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/24/17. So please
shout if anyone has objections.

Thanks.

	--yliu

---
>From 741a487b3c7c8acf29fb46e4b4019978fbb8615f Mon Sep 17 00:00:00 2001
From: John Daley <johndale at cisco.com>
Date: Wed, 1 Nov 2017 22:47:10 -0700
Subject: [PATCH] net/enic: fix TSO for packets greater than 9208 bytes

[ upstream commit cafba10bc16905b974063ae3b5feb5f3fbba991d ]

A check was previously added to drop Tx packets greater than what the Nic
is capable of sending since such packets can freeze the send queue. The
check did not account for TSO packets however, so TSO was limited to 9208
bytes.

Check packet length only for non-TSO packets. Also insure that TSO packet
segment size plus the headers do not exceed what the Nic is capable of
since this also can freeze the send queue.

Use the PKT_TX_TCP_SEG ol_flag instead of m->tso_segsz which is the
preferred way to check for TSO.

Fixes: ed6e564c214e ("net/enic: fix memory leak with oversized Tx packets")

Signed-off-by: John Daley <johndale at cisco.com>
---
 drivers/net/enic/enic_rxtx.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
index a39172f..76e023d 100644
--- a/drivers/net/enic/enic_rxtx.c
+++ b/drivers/net/enic/enic_rxtx.c
@@ -546,12 +546,15 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 	uint64_t bus_addr;
 	uint8_t offload_mode;
 	uint16_t header_len;
+	uint64_t tso;
+	rte_atomic64_t *tx_oversized;
 
 	enic_cleanup_wq(enic, wq);
 	wq_desc_avail = vnic_wq_desc_avail(wq);
 	head_idx = wq->head_idx;
 	desc_count = wq->ring.desc_count;
 	ol_flags_mask = PKT_TX_VLAN_PKT | PKT_TX_IP_CKSUM | PKT_TX_L4_MASK;
+	tx_oversized = &enic->soft_stats.tx_oversized;
 
 	nb_pkts = RTE_MIN(nb_pkts, ENIC_TX_XMIT_MAX);
 
@@ -561,10 +564,12 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 		data_len = tx_pkt->data_len;
 		ol_flags = tx_pkt->ol_flags;
 		nb_segs = tx_pkt->nb_segs;
+		tso = ol_flags & PKT_TX_TCP_SEG;
 
-		if (pkt_len > ENIC_TX_MAX_PKT_SIZE) {
+		/* drop packet if it's too big to send */
+		if (unlikely(!tso && pkt_len > ENIC_TX_MAX_PKT_SIZE)) {
 			rte_pktmbuf_free(tx_pkt);
-			rte_atomic64_inc(&enic->soft_stats.tx_oversized);
+			rte_atomic64_inc(tx_oversized);
 			continue;
 		}
 
@@ -587,13 +592,21 @@ uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 		offload_mode = WQ_ENET_OFFLOAD_MODE_CSUM;
 		header_len = 0;
 
-		if (tx_pkt->tso_segsz) {
+		if (tso) {
 			header_len = tso_header_len(tx_pkt);
-			if (header_len) {
-				offload_mode = WQ_ENET_OFFLOAD_MODE_TSO;
-				mss = tx_pkt->tso_segsz;
+
+			/* Drop if non-TCP packet or TSO seg size is too big */
+			if (unlikely(header_len == 0 || ((tx_pkt->tso_segsz +
+			    header_len) > ENIC_TX_MAX_PKT_SIZE))) {
+				rte_pktmbuf_free(tx_pkt);
+				rte_atomic64_inc(tx_oversized);
+				continue;
 			}
+
+			offload_mode = WQ_ENET_OFFLOAD_MODE_TSO;
+			mss = tx_pkt->tso_segsz;
 		}
+
 		if ((ol_flags & ol_flags_mask) && (header_len == 0)) {
 			if (ol_flags & PKT_TX_IP_CKSUM)
 				mss |= ENIC_CALC_IP_CKSUM;
-- 
2.7.4