Re: [PATCH] staging: most: video: replace BUG_ON with WARN_ON_ONCE and add recovery

[Dan Carpenter <error27@gmail.com>]

On Mon, Apr 20, 2026 at 11:35:03AM +0000, Matan Cohen wrote:
> BUG_ON() halts the kernel unconditionally. The check after
> most_deregister_component() guards against a bug in mostcore: it
> currently does not call disconnect_channel() for linked channels on
> deregistration, so if that ever changes unexpectedly, video_devices
> could be non-empty.
> 
> Replace BUG_ON with WARN_ON_ONCE so the kernel stays up, and add a
> recovery path that drains and frees any remaining devices to avoid
> memory leaks in that error case.
> 
> Also document what the spinlock and mutex in struct most_video_dev
> each protect.
> ---
>  drivers/staging/most/video/video.c | 19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/most/video/video.c b/drivers/staging/most/video/video.c
> index 04351f8ccccf1..4ade49569bd63 100644
> --- a/drivers/staging/most/video/video.c
> +++ b/drivers/staging/most/video/video.c
> @@ -33,14 +33,14 @@ struct most_video_dev {
>  	bool mute;
>  
>  	struct list_head pending_mbos;
> -	spinlock_t list_lock;
> +	spinlock_t list_lock; /* protects pending_mbos and mute */

I always dread these kinds of patches...  The comment is useless.  Way
too vague and kind of wrong also.  I want to see a much more thorough
explanation.

regards,
dan carpenter