[net 5/6] net/mlx5e: Set page to null in case dma mapping fails
From: Saeed Mahameed <hidden>
Date: 2017-11-08 07:22:20
Subsystem:
mellanox ethernet driver (mlx5e), mellanox mlx5 core vpi driver, networking drivers, the rest · Maintainers:
Saeed Mahameed, Tariq Toukan, Mark Bloch, Leon Romanovsky, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Inbar Karmy <redacted>
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 <redacted>
Reviewed-by: Tariq Toukan <redacted>
Cc: kernel-team@fb.com
Signed-off-by: Saeed Mahameed <redacted>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 15a1687483cc..91b1b0938931 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c@@ -215,22 +215,20 @@ static inline bool mlx5e_rx_cache_get(struct mlx5e_rq *rq, 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; }
--
2.14.2