[PATCH 5.14 663/849] RDMA/core: Require the driver to set the IOVA correctly during rereg_mr

Greg Kroah-Hartman
2021-11-15T23:14:09Z

From: Aharon Landau <aharonl@nvidia.com>

[ Upstream commit f1a090f09f42be5a5542009f0be310fdb3e768fc ]

If the driver returns a new MR during rereg it has to fill it with the
IOVA from the proper source. If IB_MR_REREG_TRANS is set then the IOVA is
cmd.hca_va, otherwise the IOVA comes from the old MR. mlx5 for example has
two calls inside rereg_mr:

return create_real_mr(new_pd, umem, mr->ibmr.iova,
new_access_flags);
and
return create_real_mr(new_pd, new_umem, iova, new_access_flags);

Unconditionally overwriting the iova in the newly allocated MR will
corrupt the iova if the first path is used.

Remove the redundant initializations from ib_uverbs_rereg_mr().

Fixes: 6e0954b11c05 ("RDMA/uverbs: Allow drivers to create a new HW object during rereg_mr")
Link: https://lore.kernel.org/r/4b0a31bbc372842613286a10d7a8cbb0ee6069c7.1635400472.git.leonro@nvidia.com
Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/core/uverbs_cmd.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 8c8ca7bce3caf..24dd550ceb119 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -837,11 +837,8 @@ static int ib_uverbs_rereg_mr(struct uverbs_attr_bundle *attrs)
new_mr->device = new_pd->device;
new_mr->pd = new_pd;
new_mr->type = IB_MR_TYPE_USER;
- new_mr->dm = NULL;
- new_mr->sig_attrs = NULL;
new_mr->uobject = uobj;
atomic_inc(&new_pd->usecnt);
- new_mr->iova = cmd.hca_va;
new_uobj->object = new_mr;

rdma_restrack_new(&new_mr->res, RDMA_RESTRACK_MR);
--
2.33.0