Re: [PATCH v2 1/4] sched/task: Add the put_task_struct_atomic_safe function

Wander Lairson Costa
2023-02-22T18:48:31Z

On Fri, Feb 17, 2023 at 08:04:37PM +0100, luca abeni wrote:
> Hi all,
>
> On Fri, 17 Feb 2023 14:35:22 -0300
> Daniel Bristot de Oliveira <bristot@redhat.com> wrote:
>
> > On 1/30/23 08:49, Wander Lairson Costa wrote:
> > >> Another thing, if you look at release_task_stack(), it either
> > >> caches the outgoing stack for later use, or frees it via RCU
> > >> (regardless of PREEMPT_RT). Perhaps we could follow that and just
> > >> always punt the freeing of the task struct to RCU?
> > >>
> > > That's a point. Do you mean doing that even for !PREEMPT_RT?
> > >
> >
> > It seems that Luca Abeni (in Cc) is hitting the bug in the non-rt
> > kernel with SCHED_DEADLINE...
> >
> > adding him to the thread.
>
> Thanks Daniel for adding me.
>
> I triggered this "BUG: Invalid wait context" with a 5.15.76 kernel,
> without PREEMPT_RT. I can reproduce it easily on a KVM-based VM; if
> more information or tests are needed, let me know.
>

Does it happen in linux-6.1 or linux-6.2?

>
> Luca
>