diff options
| author |   Miles Chen <miles.chen@mediatek.com> | 2017-02-22 15:40:09 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-22 16:41:26 -0800 |
| commit | a5759b2bffa807a727cbf6790ecdc4df2ae8e4d4 (patch) | |
| tree | 5173968a55e0108695940050b419cab596bc9d37 /lib | |
| parent | mm, dax: change pmd_fault() to take only vmf parameter (diff) | |
| download | linux-dev-a5759b2bffa807a727cbf6790ecdc4df2ae8e4d4.tar.xz linux-dev-a5759b2bffa807a727cbf6790ecdc4df2ae8e4d4.zip | |
dma-debug: add comment for failed to check map error
Add comment for failure to check a map error to help driver developers.
Link: http://lkml.kernel.org/r/1484622289-22085-1-git-send-email-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/dma-debug.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/lib/dma-debug.c b/lib/dma-debug.c index 8971370bfb16..60c57ec936db 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -1155,6 +1155,11 @@ static void check_unmap(struct dma_debug_entry *ref) dir2name[ref->direction]); } + /* + * Drivers should use dma_mapping_error() to check the returned + * addresses of dma_map_single() and dma_map_page(). + * If not, print this warning message. See Documentation/DMA-API.txt. + */ if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { err_printk(ref->dev, entry, "DMA-API: device driver failed to check map error" |