net/enic: fix packet loss after MTU change

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>

diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 5211670630f5c07a0520746aaa68cc671804720b..79326050434670a8881c8c53455ce5e213f40674 100644 (file)
--- 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],