Re: [PATCH v5] iio: buffer: fix warning in requesting threaded irq

Re: [PATCH v5] iio: buffer: fix warning in requesting threaded irq

[Andy Shevchenko]

On Thu, Apr 23, 2026 at 09:44:26AM +0800, Junxiao Chang wrote:
> IRQF_ONESHOT is for threaded IRQ. If there is no threaded IRQ
> handler, this flag should not be set.
> 
> This change fixes a warning during booting with kernel v7.0-rc3.
> Hardware: ARLs(Ultra 9 285) desktop
> Software: Ubuntu 24.04 + v7.0-rc3 kernel.
> 
> WARNING: kernel/irq/manage.c:1502 at __setup_irq+0x1639/0x2510, CPU#3: iio-sensor-prox/974
> Call Trace:
> request_threaded_irq+0x2c7/0x490
> iio_trigger_attach_poll_func+0x353/0x6b0
> __iio_update_buffers+0x2420/0x2c70
> enable_store+0x183/0x270
> dev_attr_store+0x5e/0x90
> 
> There is no threaded handler in thiggered buffer setup, e.g. vf610_adc

A typo here: triggered.

> and hid-sensor. They might introduce this warning.

But you see them IRL, right? Can you just add a point to the above list:

Hardware platform: ...
Hardware sensor in use: ... <— this to be added
Software stack (OS): ...

?

With that you may drop or rephrase that to

  "There is no threaded handler in triggered buffer setup in other drivers,
   e.g. vf610_adc and hid-sensor. They might introduce this warning."

> Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
> ---

...

> V3/V4: https://lore.kernel.org/linux-iio/20260421103807.7ca935e9@jic23-huawei/T/#t

('T/#t' part is not needed)

> V2: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mc0803722dce6585bbc8c9e0ec8289bd96afe99aa
> V1: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mf0eba6c23049d15c2b43ea5528b5f5a47e216c58

Click there on the permalink to get the proper link to the mail, now it's an
indirect form of the links.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v5] iio: buffer: fix warning in requesting threaded irq

[Jonathan Cameron]

On Thu, 23 Apr 2026 09:44:26 +0800
Junxiao Chang <junxiao.chang@intel.com> wrote:

> IRQF_ONESHOT is for threaded IRQ. If there is no threaded IRQ
> handler, this flag should not be set.
> 
> This change fixes a warning during booting with kernel v7.0-rc3.
> Hardware: ARLs(Ultra 9 285) desktop
> Software: Ubuntu 24.04 + v7.0-rc3 kernel.
> 
> WARNING: kernel/irq/manage.c:1502 at __setup_irq+0x1639/0x2510, CPU#3: iio-sensor-prox/974
> Call Trace:
> request_threaded_irq+0x2c7/0x490
> iio_trigger_attach_poll_func+0x353/0x6b0
> __iio_update_buffers+0x2420/0x2c70
> enable_store+0x183/0x270
> dev_attr_store+0x5e/0x90
> 
> There is no threaded handler in thiggered buffer setup, e.g. vf610_adc
> and hid-sensor. They might introduce this warning.
> 
> Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
Sashiko just did us a big favour:
https://sashiko.dev/#/patchset/20260423014426.1999735-1-junxiao.chang%40intel.com
I was making too many assumptions on what the vf610 driver was doing.
The issue here isn't in the core at all (though maybe what you are fixing
here is relevant to other drivers) it's in the vf610 driver. 

It registers a triggered buffer, but not trigger and yet actually pushes
the data from the interrupt service routine.  That is fairly nasty misuse
of the IIO infrastructure.  There are two ways to solve this.
1) Rip out the triggered buffer infrastructure and use the buffer directly.
If we need to 'pretend' that's still relevant use the same approach we used
in the hid sensors driver to keep the current_trigger interface (it just
won't do anything).
https://lore.kernel.org/all/20260220224514.471348-1-srinivas.pandruvada@linux.intel.com/
2) Actually implement a trigger. Then the isr will call iio_trigger_poll()
and the vf610_adc_read() will occur in the trigger bottom half with timestamp coming
form the top half that is currently registered.

I'd slightly prefer option 2.

Any idea what trigger your userspace is trying to use with this driver?

No idea if you are up for fixing this - if not I can have a go but have no means
to test that the driver isn't broken.  I don't have time to emulate this device
just now.

Now that's not to say there aren't drivers doing what I was assuming was happening
here (having foolishly not checked the particular driver) and registering only
a custom top half in the poll func.  For those, your fix would be the correct one.
I'm just not sure they exist.  Maybe we can merge that anyway on basis there is
a latent bug that future drivers might hit, but we should also fix the vf610 properly.

Jonathan


> ---
> V4 -> V5: remove Fixes tag and add back change log
> V3 -> V4: remove unneeded backtrace log
> V2 -> V3: remove unneeded log in git message
> V1 -> V2: use ternary and drop temp variable
> 
> V3/V4: https://lore.kernel.org/linux-iio/20260421103807.7ca935e9@jic23-huawei/T/#t
> V2: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mc0803722dce6585bbc8c9e0ec8289bd96afe99aa
> V1: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mf0eba6c23049d15c2b43ea5528b5f5a47e216c58
> 
>  drivers/iio/buffer/industrialio-triggered-buffer.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c
> index 9bf75dee7ff86..40eea3a447246 100644
> --- a/drivers/iio/buffer/industrialio-triggered-buffer.c
> +++ b/drivers/iio/buffer/industrialio-triggered-buffer.c
> @@ -64,7 +64,7 @@ int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
>  
>  	indio_dev->pollfunc = iio_alloc_pollfunc(h,
>  						 thread,
> -						 IRQF_ONESHOT,
> +						 thread ? IRQF_ONESHOT : 0,
>  						 indio_dev,
>  						 "%s_consumer%d",
>  						 indio_dev->name,

RE: [PATCH v5] iio: buffer: fix warning in requesting threaded irq

[Chang, Junxiao]

Jonathan Cameron <jonathan.cameron@huawei.com> wrote:>
>I'd slightly prefer option 2.
>
>Any idea what trigger your userspace is trying to use with this driver?
We reproduce this issue with kernel v7.0-rc3, issue should be related with hid-sensor. We just tried latest kernel(v7.0) which has integrated hid change you mentioned, issue is gone.

>
>No idea if you are up for fixing this - if not I can have a go but have no means to
>test that the driver isn't broken.  I don't have time to emulate this device just now.

I'd like to fix this, but we don't have real hardware device(vf610) for validation. ☹

>Now that's not to say there aren't drivers doing what I was assuming was
>happening here (having foolishly not checked the particular driver) and
>registering only a custom top half in the poll func.  For those, your fix would be
>the correct one.
>I'm just not sure they exist.  Maybe we can merge that anyway on basis there is a
>latent bug that future drivers might hit, but we should also fix the vf610 properly.

Similar issue exists in stm32-dfsdm-adc.c beside vf610_adc.

[PATCH v5] iio: buffer: fix warning in requesting threaded irq

[Junxiao Chang]

IRQF_ONESHOT is for threaded IRQ. If there is no threaded IRQ
handler, this flag should not be set.

This change fixes a warning during booting with kernel v7.0-rc3.
Hardware: ARLs(Ultra 9 285) desktop
Software: Ubuntu 24.04 + v7.0-rc3 kernel.

WARNING: kernel/irq/manage.c:1502 at __setup_irq+0x1639/0x2510, CPU#3: iio-sensor-prox/974
Call Trace:
request_threaded_irq+0x2c7/0x490
iio_trigger_attach_poll_func+0x353/0x6b0
__iio_update_buffers+0x2420/0x2c70
enable_store+0x183/0x270
dev_attr_store+0x5e/0x90

There is no threaded handler in thiggered buffer setup, e.g. vf610_adc
and hid-sensor. They might introduce this warning.

Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
---
V4 -> V5: remove Fixes tag and add back change log
V3 -> V4: remove unneeded backtrace log
V2 -> V3: remove unneeded log in git message
V1 -> V2: use ternary and drop temp variable

V3/V4: https://lore.kernel.org/linux-iio/20260421103807.7ca935e9@jic23-huawei/T/#t
V2: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mc0803722dce6585bbc8c9e0ec8289bd96afe99aa
V1: https://lore.kernel.org/linux-iio/20260418002334.3643504-1-junxiao.chang@intel.com/T/#mf0eba6c23049d15c2b43ea5528b5f5a47e216c58

 drivers/iio/buffer/industrialio-triggered-buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c
index 9bf75dee7ff86..40eea3a447246 100644
--- a/drivers/iio/buffer/industrialio-triggered-buffer.c
+++ b/drivers/iio/buffer/industrialio-triggered-buffer.c
@@ -64,7 +64,7 @@ int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
 
 	indio_dev->pollfunc = iio_alloc_pollfunc(h,
 						 thread,
-						 IRQF_ONESHOT,
+						 thread ? IRQF_ONESHOT : 0,
 						 indio_dev,
 						 "%s_consumer%d",
 						 indio_dev->name,
-- 
2.43.0