From dca62adebf68ec94d84444fd2a61f03f73f51ffb Mon Sep 17 00:00:00 2001
From: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Date: Tue, 1 Sep 2020 22:50:09 +0530
Subject: [PATCH] net/cxgbe: fix crash when accessing empty Tx mbuf list
Ensure packets are available before accessing the mbuf list in Tx
burst function. Otherwise, just reclaim completed Tx descriptors and
exit.
Fixes: b1df19e43e1d ("net/cxgbe: fix prefetch for non-coalesced Tx packets")
Cc: stable@dpdk.org
Reported-by: Brian Poole <brian90013@gmail.com>
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
---
drivers/net/cxgbe/cxgbe_ethdev.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/net/cxgbe/cxgbe_ethdev.c b/drivers/net/cxgbe/cxgbe_ethdev.c
index 7c6016d5cf..1205e17a6c 100644
--- a/drivers/net/cxgbe/cxgbe_ethdev.c
+++ b/drivers/net/cxgbe/cxgbe_ethdev.c
@@ -71,6 +71,9 @@ uint16_t cxgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
t4_os_lock(&txq->txq_lock);
/* free up desc from already completed tx */
reclaim_completed_tx(&txq->q);
+ if (unlikely(!nb_pkts))
+ goto out_unlock;
+
rte_prefetch0(rte_pktmbuf_mtod(tx_pkts[0], volatile void *));
while (total_sent < nb_pkts) {
pkts_remain = nb_pkts - total_sent;
@@ -91,6 +94,7 @@ uint16_t cxgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
reclaim_completed_tx(&txq->q);
}
+out_unlock:
t4_os_unlock(&txq->txq_lock);
return total_sent;
}