2019-03-06 02:51:10

by John Hubbard

Subject: [PATCH] RDMA/umem: updated bug fix in error handling path

From: John Hubbard <[email protected]>

The previous attempted bug fix overlooked the fact that
ib_umem_odp_map_dma_single_page() was doing a put_page()
upon hitting an error. So there was not really a bug there.

Therefore, this reverts the off-by-one change, but
keeps the change to use release_pages() in the error path.

Fixes: commit xxxxxxxxxxxx ("RDMA/umem: minor bug fix in error handling path")
Suggested-by: Artemy Kovalyov <[email protected]>

Cc: Leon Romanovsky <[email protected]>
Cc: Ira Weiny <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Doug Ledford <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: John Hubbard <[email protected]>
---
drivers/infiniband/core/umem_odp.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index d45735b02e07..c9cafaa080e7 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -686,10 +686,13 @@ int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 user_virt,

if (ret < 0) {
/*
- * Release pages, starting at the the first page
- * that experienced an error.
+ * Release pages, remembering that the first page
+ * to hit an error was already released by
+ * ib_umem_odp_map_dma_single_page().
*/
- release_pages(&local_page_list[j], npages - j);
+ if (npages - (j + 1) > 0)
+ release_pages(&local_page_list[j+1],
+ npages - (j + 1));
break;
}
}
--
2.21.0

2019-03-06 21:06:47

by Jason Gunthorpe

Subject: Re: [PATCH] RDMA/umem: updated bug fix in error handling path

On Tue, Mar 05, 2019 at 06:00:22PM -0800, [email protected] wrote:
> From: John Hubbard <[email protected]>
>
> The previous attempted bug fix overlooked the fact that
> ib_umem_odp_map_dma_single_page() was doing a put_page()
> upon hitting an error. So there was not really a bug there.
>
> Therefore, this reverts the off-by-one change, but
> keeps the change to use release_pages() in the error path.
>
> Fixes: commit xxxxxxxxxxxx ("RDMA/umem: minor bug fix in error handling path")
> Suggested-by: Artemy Kovalyov <[email protected]>
>
> Cc: Leon Romanovsky <[email protected]>
> Cc: Ira Weiny <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Doug Ledford <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: John Hubbard <[email protected]>
> ---
> drivers/infiniband/core/umem_odp.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)

Applied to for-next, thanks

Jason