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

From: Jonathan Cameron
Date: Sat Aug 01 2020 - 12:02:49 EST


On Mon, 27 Jul 2020 16:57:13 +0200
Christian Eggers <ceggers@xxxxxxx> wrote:

> iio_trigger_poll() calls generic_handle_irq(). This function expects to
> be run with local IRQs disabled.

Was there an error or warning that lead to this patch?
Or can you point to what call in generic_handle_irq is making the
assumption that we are breaking?

Given this is using the irq_work framework I'm wondering if this is
a more general problem?

Basically more info please!

Thanks,

Jonathan


>
> Signed-off-by: Christian Eggers <ceggers@xxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> drivers/iio/trigger/iio-trig-sysfs.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/iio/trigger/iio-trig-sysfs.c b/drivers/iio/trigger/iio-trig-sysfs.c
> index e09e58072872..66a96b1632f8 100644
> --- a/drivers/iio/trigger/iio-trig-sysfs.c
> +++ b/drivers/iio/trigger/iio-trig-sysfs.c
> @@ -94,7 +94,9 @@ static void iio_sysfs_trigger_work(struct irq_work *work)
> struct iio_sysfs_trig *trig = container_of(work, struct iio_sysfs_trig,
> work);
>
> + local_irq_disable();
> iio_trigger_poll(trig->trig);
> + local_irq_enable();
> }
>
> static ssize_t iio_sysfs_trigger_poll(struct device *dev,