[dpdk-dev] net/enic: fix packet loss after MTU change

Message ID 20171023202300.4944-1-johndale@cisco.com (mailing list archive)
State Accepted, archived
Delegated to: Ferruh Yigit
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

John Daley (johndale) Oct. 23, 2017, 8:23 p.m. UTC
  If multiple Rx queues and Rx Scatter are used and the MTU is
modified so that the number of mbufs per packet changes, packet
loss is possible.

The enic completion queue index was miscalculated leaving the
upper half of the queues uninitialized after an MTU change, possibly
leading to completions on those queues not getting processed.

Fixes: c3e09182bcd6 ("net/enic: support scatter Rx in MTU update")
Cc: stable@dpdk.org

Signed-off-by: John Daley <johndale@cisco.com>
---
 drivers/net/enic/enic_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
  

Comments

Ferruh Yigit Oct. 23, 2017, 9:36 p.m. UTC | #1
On 10/23/2017 1:23 PM, John Daley wrote:
> If multiple Rx queues and Rx Scatter are used and the MTU is
> modified so that the number of mbufs per packet changes, packet
> loss is possible.
> 
> The enic completion queue index was miscalculated leaving the
> upper half of the queues uninitialized after an MTU change, possibly
> leading to completions on those queues not getting processed.
> 
> Fixes: c3e09182bcd6 ("net/enic: support scatter Rx in MTU update")
> Cc: stable@dpdk.org
> 
> Signed-off-by: John Daley <johndale@cisco.com>

Applied to dpdk-next-net/master, thanks.
  

Patch

diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 521167063..793260504 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -1119,11 +1119,12 @@  static int
 enic_reinit_rq(struct enic *enic, unsigned int rq_idx)
 {
 	struct vnic_rq *sop_rq, *data_rq;
-	unsigned int cq_idx = enic_cq_rq(enic, rq_idx);
+	unsigned int cq_idx;
 	int rc = 0;
 
 	sop_rq = &enic->rq[enic_rte_rq_idx_to_sop_idx(rq_idx)];
 	data_rq = &enic->rq[enic_rte_rq_idx_to_data_idx(rq_idx)];
+	cq_idx = rq_idx;
 
 	vnic_cq_clean(&enic->cq[cq_idx]);
 	vnic_cq_init(&enic->cq[cq_idx],