Passing IRQF_ONESHOT ensures that the interrupt source is masked until
the secondary (threaded) handler is done. If only a primary handler is
used then the flag makes no sense because the interrupt can not fire
(again) while its handler is running.
The flag also disallows force-threading of the primary handler and the
irq-core will warn about this.
The force-threading functionality is required on PREEMPT_RT because the
handler is using locks with can sleep on PREEMPT_RT.

Remove IRQF_ONESHOT from irqflags.

Cc: Jonathan Cameron <jic23@kernel.org>
Cc: David Lechner <dlechner@baylibre.com>
Cc: "Nuno Sá" <nuno.sa@analog.com>
Cc: Andy Shevchenko <andy@kernel.org>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 drivers/iio/magnetometer/ak8975.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 3fd0171e5d69b..d30315ad85ded 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -581,7 +581,7 @@ static int ak8975_setup_irq(struct ak8975_data *data)
 		irq = gpiod_to_irq(data->eoc_gpiod);
 
 	rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
-			      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+			      IRQF_TRIGGER_RISING,
 			      dev_name(&client->dev), data);
 	if (rc < 0) {
 		dev_err(&client->dev, "irq %d request failed: %d\n", irq, rc);
-- 
2.51.0

On Fri, 2026-01-23 at 12:37 +0100, Sebastian Andrzej Siewior wrote:
> Passing IRQF_ONESHOT ensures that the interrupt source is masked until
> the secondary (threaded) handler is done. If only a primary handler is
> used then the flag makes no sense because the interrupt can not fire
> (again) while its handler is running.
> The flag also disallows force-threading of the primary handler and the
> irq-core will warn about this.
> The force-threading functionality is required on PREEMPT_RT because the
> handler is using locks with can sleep on PREEMPT_RT.
> 
> Remove IRQF_ONESHOT from irqflags.
> 
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: David Lechner <dlechner@baylibre.com>
> Cc: "Nuno Sá" <nuno.sa@analog.com>
> Cc: Andy Shevchenko <andy@kernel.org>
> Cc: linux-iio@vger.kernel.org
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> ---

Reviewed-by: Nuno Sá <nuno.sa@analog.com>

>  drivers/iio/magnetometer/ak8975.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
> index 3fd0171e5d69b..d30315ad85ded 100644
> --- a/drivers/iio/magnetometer/ak8975.c
> +++ b/drivers/iio/magnetometer/ak8975.c
> @@ -581,7 +581,7 @@ static int ak8975_setup_irq(struct ak8975_data *data)
>  		irq = gpiod_to_irq(data->eoc_gpiod);
>  
>  	rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler,
> -			      IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> +			      IRQF_TRIGGER_RISING,
>  			      dev_name(&client->dev), data);
>  	if (rc < 0) {
>  		dev_err(&client->dev, "irq %d request failed: %d\n", irq, rc);

On Wed, Jan 28, 2026 at 11:40:56AM +0000, Nuno Sá wrote:
> On Fri, 2026-01-23 at 12:37 +0100, Sebastian Andrzej Siewior wrote:

> Reviewed-by: Nuno Sá <nuno.sa@analog.com>

There is the v2 available.

-- 
With Best Regards,
Andy Shevchenko

	Hi Sebastian,

> Passing IRQF_ONESHOT ensures that the interrupt source is masked until
> the secondary (threaded) handler is done. If only a primary handler is
> used then the flag makes no sense because the interrupt can not fire
> (again) while its handler is running.
> The flag also disallows force-threading of the primary handler and the
> irq-core will warn about this.
> The force-threading functionality is required on PREEMPT_RT because the
> handler is using locks with can sleep on PREEMPT_RT.
> 
> Remove IRQF_ONESHOT from irqflags.
> 
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: David Lechner <dlechner@baylibre.com>
> Cc: "Nuno Sá" <nuno.sa@analog.com>
> Cc: Andy Shevchenko <andy@kernel.org>
> Cc: linux-iio@vger.kernel.org
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Thanks for your patch!

This fixes the

    WARNING: kernel/irq/manage.c:1491 at __setup_irq+0xb0/0x79c, CPU#0: swapper/0/1

I was seeing on the KZM-A9-GT board since commit aef30c8d569c0f31
("genirq: Warn about using IRQF_ONESHOT without a threaded handler") in
irqchip/irq/core.

Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

On Fri, Jan 23, 2026 at 12:37:06PM +0100, Sebastian Andrzej Siewior wrote:
> Passing IRQF_ONESHOT ensures that the interrupt source is masked until
> the secondary (threaded) handler is done. If only a primary handler is
> used then the flag makes no sense because the interrupt can not fire
> (again) while its handler is running.
> The flag also disallows force-threading of the primary handler and the
> irq-core will warn about this.
> The force-threading functionality is required on PREEMPT_RT because the
> handler is using locks with can sleep on PREEMPT_RT.
> 
> Remove IRQF_ONESHOT from irqflags.

...

> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: David Lechner <dlechner@baylibre.com>
> Cc: "Nuno Sá" <nuno.sa@analog.com>
> Cc: Andy Shevchenko <andy@kernel.org>
> Cc: linux-iio@vger.kernel.org

Same comment on the location of Cc list.

-- 
With Best Regards,
Andy Shevchenko