diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 575b78045aaf..c5b94d647e1e 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1183,23 +1183,33 @@ EXPORT_SYMBOL(ib_dealloc_fmr);
 
 int ib_attach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 {
+	int ret;
+
 	if (!qp->device->attach_mcast)
 		return -ENOSYS;
 	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
 		return -EINVAL;
 
-	return qp->device->attach_mcast(qp, gid, lid);
+	ret = qp->device->attach_mcast(qp, gid, lid);
+	if (!ret)
+		atomic_inc(&qp->usecnt);
+	return ret;
 }
 EXPORT_SYMBOL(ib_attach_mcast);
 
 int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 {
+	int ret;
+
 	if (!qp->device->detach_mcast)
 		return -ENOSYS;
 	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
 		return -EINVAL;
 
-	return qp->device->detach_mcast(qp, gid, lid);
+	ret = qp->device->detach_mcast(qp, gid, lid);
+	if (!ret)
+		atomic_dec(&qp->usecnt);
+	return ret;
 }
 EXPORT_SYMBOL(ib_detach_mcast);
 
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index c3cca5a4dacd..c84d1016618e 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -964,7 +964,7 @@ struct ib_qp {
 	struct ib_srq	       *srq;
 	struct ib_xrcd	       *xrcd; /* XRC TGT QPs only */
 	struct list_head	xrcd_list;
-	atomic_t		usecnt; /* count times opened */
+	atomic_t		usecnt; /* count times opened, mcast attaches */
 	struct list_head	open_list;
 	struct ib_qp           *real_qp;
 	struct ib_uobject      *uobject;