IB/mlx4: Don't overwrite fast registration page list when posting work request

The low-level mlx4 driver modified the page-list addresses for fast
register work requests post send to big-endian, and set a "present"
bit.  This caused problems later when the consumer attempted to unmap
the pages using the page-list (using the list addresses which were
assumed to be still in CPU-endian order).  Fix the mlx4 driver to
allocate two buffers and use a private buffer for the hardware-format
bus addresses.

This patch fixes <https://bugs.openfabrics.org/show_bug.cgi?id=1571>,
an NFS/RDMA server crash.  The cause of the crash was found by Vu Pham
of Mellanox.  The fix is along the lines suggested by Steve Wise in
comment #21 in bug 1571.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index f385a24d31d2..20724aee76f4 100644
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -1365,7 +1365,7 @@ static void set_fmr_seg(struct mlx4_wqe_fmr_seg *fseg, struct ib_send_wr *wr)
         int i;
 
         for (i = 0; i < wr->wr.fast_reg.page_list_len; ++i)
-                wr->wr.fast_reg.page_list->page_list[i] =
+                mfrpl->mapped_page_list[i] =
                         cpu_to_be64(wr->wr.fast_reg.page_list->page_list[i] |
                                     MLX4_MTT_FLAG_PRESENT);