The behaviour of kthread_create_worker() was recently changed to align with the one of kthread_create(). The kthread worker is created but not awaken by default. This is to allow the use of kthread_affine_preferred() and kthread_bind[_mask]() with kthread workers. In order to keep the old behaviour and wake the kthread up, kthread_run_worker() must be used. All the pre-existing users have been converted, except for UVC that was introduced in the same merge window as the API change. This results in hangs: INFO: task UVCG:82 blocked for more than 491 seconds. Tainted: G T 6.13.0-rc2-00014-gb04e317b5226 #1 task:UVCG state:D stack:0 pid:82 Call Trace: __schedule schedule schedule_preempt_disabled kthread ? kthread_flush_work ret_from_fork ret_from_fork_asm entry_INT80_32 Fix this with converting UVCG kworker to the new API. Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Closes: https://lore.kernel.org/oe-lkp/202502121025.55bfa801-lkp@xxxxxxxxx Fixes: f0bbfbd16b3b ("usb: gadget: uvc: rework to enqueue in pump worker from encoded queue") Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx> --- drivers/usb/gadget/function/uvc_video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 79e223713d8b..fb77b0b21790 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -818,7 +818,7 @@ int uvcg_video_init(struct uvc_video *video, struct uvc_device *uvc) return -EINVAL; /* Allocate a kthread for asynchronous hw submit handler. */ - video->kworker = kthread_create_worker(0, "UVCG"); + video->kworker = kthread_run_worker(0, "UVCG"); if (IS_ERR(video->kworker)) { uvcg_err(&video->uvc->func, "failed to create UVCG kworker\n"); return PTR_ERR(video->kworker); -- 2.46.0
