1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_cq.c b/drivers/infiniband/hw/ipath/ipath_cq.c
index 9014ef63eedc..a6f04d27ec57 100644
--- a/drivers/infiniband/hw/ipath/ipath_cq.c
+++ b/drivers/infiniband/hw/ipath/ipath_cq.c
@@ -90,6 +90,8 @@ void ipath_cq_enter(struct ipath_cq *cq, struct ib_wc *entry, int solicited)
         wc->queue[head].sl = entry->sl;
         wc->queue[head].dlid_path_bits = entry->dlid_path_bits;
         wc->queue[head].port_num = entry->port_num;
+        /* Make sure queue entry is written before the head index. */
+        smp_wmb();
         wc->head = next;
 
         if (cq->notify == IB_CQ_NEXT_COMP ||
@@ -139,7 +141,8 @@ int ipath_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry)
 
                 if (tail == wc->head)
                         break;
-
+                /* Make sure entry is read after head index is read. */
+                smp_rmb();
                 qp = ipath_lookup_qpn(&to_idev(cq->ibcq.device)->qp_table,
                                       wc->queue[tail].qp_num);
                 entry->qp = &qp->ibqp;