This is a note to let you know that I've just added the patch titled
media: camss: Clean up received buffers on failed start of streaming
to the 5.4-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:
media-camss-clean-up-received-buffers-on-failed-star.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 69d31cb322e890f9c7c9d4e4a8f1f6bce287cdaa
Author: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
Date: Mon Jul 4 10:44:37 2022 +0100
media: camss: Clean up received buffers on failed start of streaming
[ Upstream commit c8f3582345e6a69da65ab588f7c4c2d1685b0e80 ]
It is required to return the received buffers, if streaming can not be
started. For instance media_pipeline_start() may fail with EPIPE, if
a link validation between entities is not passed, and in such a case
a user gets a kernel warning:
WARNING: CPU: 1 PID: 520 at drivers/media/common/videobuf2/videobuf2-core.c:1592 vb2_start_streaming+0xec/0x160
<snip>
Call trace:
vb2_start_streaming+0xec/0x160
vb2_core_streamon+0x9c/0x1a0
vb2_ioctl_streamon+0x68/0xbc
v4l_streamon+0x30/0x3c
__video_do_ioctl+0x184/0x3e0
video_usercopy+0x37c/0x7b0
video_ioctl2+0x24/0x40
v4l2_ioctl+0x4c/0x70
The fix is to correct the error path in video_start_streaming() of camss.
Fixes: 0ac2586c410f ("media: camss: Add files which handle the video device nodes")
Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/media/platform/qcom/camss/camss-video.c b/drivers/media/platform/qcom/camss/camss-video.c
index 4c2675b43718..6a5ec133a957 100644
--- a/drivers/media/platform/qcom/camss/camss-video.c
+++ b/drivers/media/platform/qcom/camss/camss-video.c
@@ -438,7 +438,7 @@ static int video_start_streaming(struct vb2_queue *q, unsigned int count)
ret = media_pipeline_start(&vdev->entity, &video->pipe);
if (ret < 0)
- return ret;
+ goto flush_buffers;
ret = video_check_format(video);
if (ret < 0)
@@ -467,6 +467,7 @@ static int video_start_streaming(struct vb2_queue *q, unsigned int count)
error:
media_pipeline_stop(&vdev->entity);
+flush_buffers:
video->ops->flush_buffers(video, VB2_BUF_STATE_QUEUED);
return ret;
