Re: [PATCH] iio: trigger: sysfs: Disable irqs before calling iio_trigger_poll()

From: Christian Eggers
Date: Mon Aug 03 2020 - 02:45:14 EST


Hi Lars,

On Monday, 3 August 2020, 08:37:43 CEST, Lars-Peter Clausen wrote:
> The sysfs IIO trigger uses irq_work to schedule the iio_trigger_poll()
> and the promise of irq_work is that the callback will run in hard IRQ
> context. That's the whole point of it.
>
> irq_work_run_list(), which shows up in your callgraph, has as
> BUG_ON(!irqs_disabled())[1], so we should never even get to calling
> iio_trigger_poll() if IRQs where not disabled at this point. That's the
> same condition that triggers the WARN_ON() in __handle_irq_event_percpu.
is my patch sufficient, or would you prefer a different solution?

> Are you using a non-upstream kernel? Maybe a RT kernel?
I use v5.4.<almost-latest>-rt

regards
Christian