[dpdk-dev] [PATCH] net/ena: fix releasing Tx ring mbufs

[David Harton]

When ena_tx_queue_release_bufs() frees the mbufs it does not clear
the mbuf pointers.  So, when the device starts and stops multiple
times it can cause the application to receive duplicate mbufs for
two different packets.  Fix the issue by clearing the mbuf pointer.

Also, while tracking down the "double free" issue the ena calls to
allocate and free mbufs in bulk were migrated to the mbuf based APIs
so the common mbuf alloc/free routines are exercised.

Fixes: 79405ee17585 ("net/ena: fix out of order completion")
Fixes: 1173fca25af9 ("ena: add polling-mode driver")

Signed-off-by: David Harton <dharton at cisco.com>
---
 drivers/net/ena/ena_ethdev.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index 9aa51c9dc..222f2510e 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -767,8 +767,10 @@ static void ena_tx_queue_release_bufs(struct ena_ring *ring)
 	for (i = 0; i < ring->ring_size; ++i) {
 		struct ena_tx_buffer *tx_buf = &ring->tx_buffer_info[i];
 
-		if (tx_buf->mbuf)
+		if (tx_buf->mbuf) {
 			rte_pktmbuf_free(tx_buf->mbuf);
+			tx_buf->mbuf = NULL;
+		}
 	}
 }
 
@@ -1457,7 +1459,7 @@ static int ena_populate_rx_queue(struct ena_ring *rxq, unsigned int count)
 		"bad ring state\n");
 
 	/* get resources for incoming packets */
-	rc = rte_mempool_get_bulk(rxq->mb_pool, (void **)mbufs, count);
+	rc = rte_pktmbuf_alloc_bulk(rxq->mb_pool, (void **)mbufs, count);
 	if (unlikely(rc < 0)) {
 		rte_atomic64_inc(&rxq->adapter->drv_stats->rx_nombuf);
 		++rxq->rx_stats.mbuf_alloc_fail;
@@ -1486,7 +1488,7 @@ static int ena_populate_rx_queue(struct ena_ring *rxq, unsigned int count)
 	if (unlikely(i < count)) {
 		PMD_DRV_LOG(WARNING, "refilled rx qid %d with only %d "
 			"buffers (from %d)\n", rxq->id, i, count);
-		rte_mempool_put_bulk(rxq->mb_pool, (void **)(&mbufs[i]),
+		rte_pktmbuf_alloc_bulk(rxq->mb_pool, (void **)(&mbufs[i]),
 				     count - i);
 		++rxq->rx_stats.refill_partial;
 	}
-- 
2.26.2.Cisco