ib_isert: Add max_send_sge=2 minimum for control PDU responses

[cascardo/linux.git] / drivers / infiniband / ulp / isert / ib_isert.c

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 3effa93..ef5b22b 100644 (file)
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -115,9 +115,12 @@ isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id,
        attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS;
        /*
         * FIXME: Use devattr.max_sge - 2 for max_send_sge as
-        * work-around for RDMA_READ..
+        * work-around for RDMA_READs with ConnectX-2.
+        *
+        * Also, still make sure to have at least two SGEs for
+        * outgoing control PDU responses.
         */
-       attr.cap.max_send_sge = device->dev_attr.max_sge - 2;
+       attr.cap.max_send_sge = max(2, device->dev_attr.max_sge - 2);
        isert_conn->max_sge = attr.cap.max_send_sge;
 
        attr.cap.max_recv_sge = 1;