This is a note to let you know that I've just added the patch titled
dma-mapping: benchmark: avoid needless copy_to_user if benchmark fails
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dma-mapping-benchmark-avoid-needless-copy_to_user-if.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 21368ad67f9c28722f8bbc3706661998856dd58c
Author: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Date: Sat May 4 14:47:02 2024 +0300
dma-mapping: benchmark: avoid needless copy_to_user if benchmark fails
[ Upstream commit f7c9ccaadffd13066353332c13d7e9bf73b8f92d ]
If do_map_benchmark() has failed, there is nothing useful to copy back
to userspace.
Suggested-by: Barry Song <21cnbao@xxxxxxxxx>
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Acked-by: Robin Murphy <robin.murphy@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index b7f8bb7a1e5c5..fc67b39d8b38a 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -275,6 +275,9 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
* dma_mask changed by benchmark
*/
dma_set_mask(map->dev, old_dma_mask);
+
+ if (ret)
+ return ret;
break;
default:
return -EINVAL;
