From: Michal Pecio michal.pecio@gmail.com

Return buffers if streaming fails to start due to uvc_pm_get() error.

This bug may be responsible for a warning I got running

while :; do yavta -c3 /dev/video0; done

on an xHCI controller which failed under this workload. I had no luck reproducing this warning again to confirm.

xhci_hcd 0000:09:00.0: HC died; cleaning up usb 13-2: USB disconnect, device number 2 WARNING: CPU: 2 PID: 29386 at drivers/media/common/videobuf2/videobuf2-core.c:1803 vb2_start_streaming+0xac/0x120

Fixes: 7dd56c47784a ("media: uvcvideo: Remove stream->is_streaming field") Cc: stable@vger.kernel.org Signed-off-by: Michal Pecio michal.pecio@gmail.com Reviewed-by: Ricardo Ribalda ribalda@chromium.org Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Link: https://patch.msgid.link/20251015133642.3dede646.michal.pecio@gmail.com Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- Changes since v1:

- Reorganize error path --- drivers/media/usb/uvc/uvc_queue.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c index 790184c9843d..e838c6c1893a 100644 --- a/drivers/media/usb/uvc/uvc_queue.c +++ b/drivers/media/usb/uvc/uvc_queue.c @@ -177,18 +177,20 @@ static int uvc_start_streaming_video(struct vb2_queue *vq, unsigned int count)

ret = uvc_pm_get(stream->dev); if (ret) - return ret; + goto err_buffers;

queue->buf_used = 0;

ret = uvc_video_start_streaming(stream); - if (ret == 0) - return 0; + if (ret) + goto err_pm;

+ return 0; + +err_pm: uvc_pm_put(stream->dev); - +err_buffers: uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED); - return ret; }

base-commit: d363bdfa0ec6b19a4f40b572cec70430d5b13ad6