IB/mlx4: Check if GRH is available before using it

Before reading GRH attributes, need to make sure AH contains GRH,
and in addition, initialize GID type.

Fixes: dbf727de7440 ('IB/core: Use GID table in AH creation and dmac resolution')
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index 570bc866b1d62251f0ac50dc8c99606d57beedfd..0914731c9aac659c5274ab305c7251857ea15d36 100644 (file)
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -1764,14 +1764,14 @@ static int __mlx4_ib_modify_qp(struct ib_qp *ibqp,
                u8 port_num = mlx4_is_bonded(to_mdev(ibqp->device)->dev) ? 1 :
                        attr_mask & IB_QP_PORT ? attr->port_num : qp->port;
                union ib_gid gid;
-               struct ib_gid_attr gid_attr;
+               struct ib_gid_attr gid_attr = {.gid_type = IB_GID_TYPE_IB};
                u16 vlan = 0xffff;
                u8 smac[ETH_ALEN];
                int status = 0;
                int is_eth = rdma_cap_eth_ah(&dev->ib_dev, port_num) &&
                        attr->ah_attr.ah_flags & IB_AH_GRH;
 
-               if (is_eth) {
+               if (is_eth && attr->ah_attr.ah_flags & IB_AH_GRH) {
                        int index = attr->ah_attr.grh.sgid_index;
 
                        status = ib_get_cached_gid(ibqp->device, port_num,