3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Or Gerlitz <ogerlitz@xxxxxxxxxxxx> commit f57915cfa5b2b14c1cffa2e83c034f55e3f0e70d upstream. This patch adds a max_send_sge=2 minimum in isert_conn_setup_qp() to ensure outgoing control PDU responses with tx_desc->num_sge=2 are able to function correctly. This addresses a bug with RDMA hardware using dev_attr.max_sge=3, that in the original code with the ConnectX-2 work-around would result in isert_conn->max_sge=1 being negotiated. Originally reported by Chris with ocrdma driver. Reported-by: Chris Moore <Chris.Moore@xxxxxxxxxx> Tested-by: Chris Moore <Chris.Moore@xxxxxxxxxx> Signed-off-by: Or Gerlitz <ogerlitz@xxxxxxxxxxxx> Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/ulp/isert/ib_isert.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -107,9 +107,12 @@ isert_conn_setup_qp(struct isert_conn *i 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 = devattr.max_sge - 2; + attr.cap.max_send_sge = max(2, devattr.max_sge - 2); isert_conn->max_sge = attr.cap.max_send_sge; attr.cap.max_recv_sge = 1; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html