4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Inbar Karmy <inbark@xxxxxxxxxxxx> [ 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@xxxxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx> Cc: kernel-team@xxxxxx Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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; }