lkml.org 
[lkml]   [2017]   [Nov]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.13 16/35] net/mlx5e: Set page to null in case dma mapping fails
Date
4.13-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Inbar Karmy <inbark@mellanox.com>


[ Upstream commit 2e50b2619538ea0224c037f6fa746023089e0654 ]

Currently, when dma mapping fails, put_page is called,
but the page is not set to null. Later, in the page_reuse treatment in
mlx5e_free_rx_descs(), mlx5e_page_release() is called for the second time,
improperly doing dma_unmap (for a non-mapped address) and an extra put_page.
Prevent this by nullifying the page pointer when dma_map fails.

Fixes: accd58833237 ("net/mlx5e: Introduce RX Page-Reuse")
Signed-off-by: Inbar Karmy <inbark@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Cc: kernel-team@fb.com
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -213,22 +213,20 @@ static inline bool mlx5e_rx_cache_get(st
static inline int mlx5e_page_alloc_mapped(struct mlx5e_rq *rq,
struct mlx5e_dma_info *dma_info)
{
- struct page *page;
-
if (mlx5e_rx_cache_get(rq, dma_info))
return 0;

- page = dev_alloc_pages(rq->buff.page_order);
- if (unlikely(!page))
+ dma_info->page = dev_alloc_pages(rq->buff.page_order);
+ if (unlikely(!dma_info->page))
return -ENOMEM;

- dma_info->addr = dma_map_page(rq->pdev, page, 0,
+ dma_info->addr = dma_map_page(rq->pdev, dma_info->page, 0,
RQ_PAGE_SIZE(rq), rq->buff.map_dir);
if (unlikely(dma_mapping_error(rq->pdev, dma_info->addr))) {
- put_page(page);
+ put_page(dma_info->page);
+ dma_info->page = NULL;
return -ENOMEM;
}
- dma_info->page = page;

return 0;
}

\
 
 \ /
  Last update: 2017-11-22 11:16    [W:0.145 / U:4.192 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site