Re: [Patch v4 10/10] i2x: pnx: Use threaded irq to fix warning from del_timer_sync()

Piotr Wojtaszczyk
2024-06-21T12:08:14Z

Hi Andi,

On Fri, Jun 21, 2024 at 12:57 AM Andi Shyti <andi.shyti@kernel.org> wrote:
> On Thu, Jun 20, 2024 at 07:56:41PM GMT, Piotr Wojtaszczyk wrote:
> > When del_timer_sync() is called in an interrupt context it throws a warning
> > because of potential deadlock. Threaded irq handler fixes the potential
> > problem.
> >
> > Signed-off-by: Piotr Wojtaszczyk <piotr.wojtaszczyk@timesys.com>
>
> did you run into a lockdep splat?
>
> Anything against using del_timer(), instead? Have you tried?

I didn't get a lockdep splat but console was flooded with warnings from
https://github.com/torvalds/linux/blob/v6.10-rc4/kernel/time/timer.c#L1655
In the linux kernel v5.15 I didn't see these warnings.

I'm not a maintainer of the driver and I didn't do any research on
what kind of impact
would have using del_timer() instad. Maybe Vladimir Zapolskiy will know that.

--
Piotr Wojtaszczyk
Timesys