Re: [PATCH] kthread: remove worker->task self-assignment

[Bradley Morgan <brads@mainlining.org>]

On 1 September 2026 15:06:51 BST, Frederic Weisbecker <frederic@kernel.org>
wrote:
>Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
>> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
>> wrote:
>> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>> >> Hi,
>> >> 
>> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>> >> > From: Bradley Morgan <brads@mainlining.org>
>> >> > 
>> >> > All kthread worker users now create their workers with
>> >> > kthread_create_worker*(), which sets worker->task before the worker
>> >> > starts. The self-assignment in kthread_worker_fn() is dead code
>now.
>> >> 
>> >> How could it be created before?
>> >> 
>> >> > 
>> >> > Remove it.
>> >> > 
>> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>> >> > ---
>> >> >  kernel/kthread.c | 7 -------
>> >> >  1 file changed, 7 deletions(-)
>> >> > 
>> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>> >> > index 63beb59b7a3d..18bc702e8d2d 100644
>> >> > --- a/kernel/kthread.c
>> >> > +++ b/kernel/kthread.c
>> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>> >> >  	struct kthread_worker *worker = worker_ptr;
>> >> >  	struct kthread_work *work;
>> >> >  
>> >> > -	/*
>> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
>> >> > -	 * worker users are created using kthread_create_worker*() functions.
>> >> > -	 */
>> >> > -	WARN_ON(worker->task && worker->task != current);
>> >> 
>> >> Should we keep a WARN_ON(worker->task != current) here?
>> >
>> >I vote yes! Paranoia is good :-)
>> >
>> 
>> 
>> Yeah, but it *should* be useless.
>
>Famous last words :-)
>
>> Do you really want me to readd the warn
>> statement? Maybe add some text, like
>> 
>> "worker->task is deprecated"?
>
>Is it deprecated? We still need that field for wakeup on queue at least.
>Don't bother with a message, it's only a sanity check.
>
>Thanks.

Hi, I hopped on the computer, 

Right, so the whole warn on things is good, but I converted all the
callers, so it'll never fire.

For OOT users, maybe this'll be beneficial (but yk what their like, theyll
remove the warn on)

Guys, what do you think?

>
>> 
>> --- Thanks!
>>
>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
>
>

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/