On 7/4/22 12:44, Vladimir Zapolskiy wrote:
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>
---
Gentle ping, it would be great to see this fix on media/fixes for 6.0.
drivers/media/platform/qcom/camss/camss-video.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/media/platform/qcom/camss/camss-video.c b/drivers/media/platform/qcom/camss/camss-video.c
index b5f12ec5c50c..d272ffa02112 100644
--- a/drivers/media/platform/qcom/camss/camss-video.c
+++ b/drivers/media/platform/qcom/camss/camss-video.c
@@ -495,7 +495,7 @@ 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)
@@ -524,6 +524,7 @@ 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;
--
Best wishes,
Vladimir
