1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_cq.c b/drivers/infiniband/hw/mthca/mthca_cq.c
index e393681ba7d4..149b36901239 100644
--- a/drivers/infiniband/hw/mthca/mthca_cq.c
+++ b/drivers/infiniband/hw/mthca/mthca_cq.c
@@ -39,6 +39,8 @@
 #include <linux/init.h>
 #include <linux/hardirq.h>
 
+#include <asm/io.h>
+
 #include <rdma/ib_pack.h>
 
 #include "mthca_dev.h"
@@ -210,6 +212,11 @@ static inline void update_cons_index(struct mthca_dev *dev, struct mthca_cq *cq,
                 mthca_write64(doorbell,
                               dev->kar + MTHCA_CQ_DOORBELL,
                               MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
+                /*
+                 * Make sure doorbells don't leak out of CQ spinlock
+                 * and reach the HCA out of order:
+                 */
+                mmiowb();
         }
 }