Re: [PATCH v3 1/5] media: mc: add manual request completion

Nicolas Dufresne
2025-06-05T12:45:11Z

Hi Hans, Sakari,

Le jeudi 05 juin 2025 à 09:48 +0000, Sakari Ailus a écrit :
> > It's not user-triggerable, if this happens, then it is a driver bug.
>
> If there is a driver bug, it could well be user-triggerable, wouldn't it?
> Testing may not uncover all such cases.

You are both right, if the driver is not used, the warning will never
trigger. I was worried of the hit of a thread safe ONCE implementation,
but WARN_ONCE is simply not, it can warn few time before it stops if
called from multiple CPUs at the same time. In that specific function,
I can move all the checks inside the lock to make it truly once.

Now its up to you, I don't have strong preference. These are driver errors,
and usually quite critical. They are not bug_on simply because we have a
crash free resolution, but its probably not functional anymore.

Nicolas