IB/mlx4: Set umem field to NULL in mlx4_ib_alloc_fast_reg_mr()

Set mr->umem to NULL in mlx4_ib_alloc_fast_reg_mr(). Otherwise
ib_dereg_mr() may invoke ib_umem_release() on a random pointer value
and get an oops.

Signed-off-by: Vladimir Sokolovsky <vlad@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/mlx4/mr.c b/drivers/infiniband/hw/mlx4/mr.c
index 87f5c5a87b98..8e4d26d56a95 100644
--- a/drivers/infiniband/hw/mlx4/mr.c
+++ b/drivers/infiniband/hw/mlx4/mr.c
@@ -205,6 +205,7 @@ struct ib_mr *mlx4_ib_alloc_fast_reg_mr(struct ib_pd *pd,
                 goto err_mr;
 
         mr->ibmr.rkey = mr->ibmr.lkey = mr->mmr.key;
+        mr->umem = NULL;
 
         return &mr->ibmr;