1. Patchew
  2. linux
  3. View series

[PATCH] pinctrl: qcom: lpass-lpi: mark the GPIO controller as sleeping

Bartosz Golaszewski posted 1 patch 5 days, 9 hours ago 
drivers/pinctrl/qcom/pinctrl-lpass-lpi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] pinctrl: qcom: lpass-lpi: mark the GPIO controller as sleeping
Posted by Bartosz Golaszewski 5 days, 9 hours ago 
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

The gpio_chip settings in this driver say the controller can't sleep
but it actually uses a mutex for synchronization. This triggers the
following BUG():

[    9.233659] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281
[    9.233665] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 554, name: (udev-worker)
[    9.233669] preempt_count: 1, expected: 0
[    9.233673] RCU nest depth: 0, expected: 0
[    9.233688] Tainted: [W]=WARN
[    9.233690] Hardware name: Dell Inc. Latitude 7455/0FK7MX, BIOS 2.10.1 05/20/2025
[    9.233694] Call trace:
[    9.233696]  show_stack+0x24/0x38 (C)
[    9.233709]  dump_stack_lvl+0x40/0x88
[    9.233716]  dump_stack+0x18/0x24
[    9.233722]  __might_resched+0x148/0x160
[    9.233731]  __might_sleep+0x38/0x98
[    9.233736]  mutex_lock+0x30/0xd8
[    9.233749]  lpi_config_set+0x2e8/0x3c8 [pinctrl_lpass_lpi]
[    9.233757]  lpi_gpio_direction_output+0x58/0x90 [pinctrl_lpass_lpi]
[    9.233761]  gpiod_direction_output_raw_commit+0x110/0x428
[    9.233772]  gpiod_direction_output_nonotify+0x234/0x358
[    9.233779]  gpiod_direction_output+0x38/0xd0
[    9.233786]  gpio_shared_proxy_direction_output+0xb8/0x2a8 [gpio_shared_proxy]
[    9.233792]  gpiod_direction_output_raw_commit+0x110/0x428
[    9.233799]  gpiod_direction_output_nonotify+0x234/0x358
[    9.233806]  gpiod_configure_flags+0x2c0/0x580
[    9.233812]  gpiod_find_and_request+0x358/0x4f8
[    9.233819]  gpiod_get_index+0x7c/0x98
[    9.233826]  devm_gpiod_get+0x34/0xb0
[    9.233829]  reset_gpio_probe+0x58/0x128 [reset_gpio]
[    9.233836]  auxiliary_bus_probe+0xb0/0xf0
[    9.233845]  really_probe+0x14c/0x450
[    9.233853]  __driver_probe_device+0xb0/0x188
[    9.233858]  driver_probe_device+0x4c/0x250
[    9.233863]  __driver_attach+0xf8/0x2a0
[    9.233868]  bus_for_each_dev+0xf8/0x158
[    9.233872]  driver_attach+0x30/0x48
[    9.233876]  bus_add_driver+0x158/0x2b8
[    9.233880]  driver_register+0x74/0x118
[    9.233886]  __auxiliary_driver_register+0x94/0xe8
[    9.233893]  init_module+0x34/0xfd0 [reset_gpio]
[    9.233898]  do_one_initcall+0xec/0x300
[    9.233903]  do_init_module+0x64/0x260
[    9.233910]  load_module+0x16c4/0x1900
[    9.233915]  __arm64_sys_finit_module+0x24c/0x378
[    9.233919]  invoke_syscall+0x4c/0xe8
[    9.233925]  el0_svc_common+0x8c/0xf0
[    9.233929]  do_el0_svc+0x28/0x40
[    9.233934]  el0_svc+0x38/0x100
[    9.233938]  el0t_64_sync_handler+0x84/0x130
[    9.233943]  el0t_64_sync+0x17c/0x180

Mark the controller as sleeping.

Fixes: 6e261d1090d6 ("pinctrl: qcom: Add sm8250 lpass lpi pinctrl driver")
Cc: stable@vger.kernel.org
Reported-by: Val Packett <val@packett.cool>
Closes: https://lore.kernel.org/all/98c0f185-b0e0-49ea-896c-f3972dd011ca@packett.cool/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/pinctrl/qcom/pinctrl-lpass-lpi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
index 1c97ec44aa5ff..78212f9928430 100644
--- a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
+++ b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
@@ -498,7 +498,7 @@ int lpi_pinctrl_probe(struct platform_device *pdev)
 	pctrl->chip.base = -1;
 	pctrl->chip.ngpio = data->npins;
 	pctrl->chip.label = dev_name(dev);
-	pctrl->chip.can_sleep = false;
+	pctrl->chip.can_sleep = true;
 
 	mutex_init(&pctrl->lock);
 
-- 
2.51.0
Re: [PATCH] pinctrl: qcom: lpass-lpi: mark the GPIO controller as sleeping
Posted by Dmitry Baryshkov 5 days, 7 hours ago 
On Wed, Nov 26, 2025 at 01:22:19PM +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> The gpio_chip settings in this driver say the controller can't sleep
> but it actually uses a mutex for synchronization. This triggers the
> following BUG():
> 
> [    9.233659] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281

Nit: usually you can strip timestamps from the kernel dump.

Other than that:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>


> [    9.233665] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 554, name: (udev-worker)

-- 
With best wishes
Dmitry
Re: [PATCH] pinctrl: qcom: lpass-lpi: mark the GPIO controller as sleeping
Posted by Bjorn Andersson 5 days, 7 hours ago 
On Wed, Nov 26, 2025 at 01:22:19PM +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> The gpio_chip settings in this driver say the controller can't sleep
> but it actually uses a mutex for synchronization. This triggers the
> following BUG():
> 
> [    9.233659] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281
> [    9.233665] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 554, name: (udev-worker)
> [    9.233669] preempt_count: 1, expected: 0
> [    9.233673] RCU nest depth: 0, expected: 0
> [    9.233688] Tainted: [W]=WARN
> [    9.233690] Hardware name: Dell Inc. Latitude 7455/0FK7MX, BIOS 2.10.1 05/20/2025
> [    9.233694] Call trace:
> [    9.233696]  show_stack+0x24/0x38 (C)
> [    9.233709]  dump_stack_lvl+0x40/0x88
> [    9.233716]  dump_stack+0x18/0x24
> [    9.233722]  __might_resched+0x148/0x160
> [    9.233731]  __might_sleep+0x38/0x98
> [    9.233736]  mutex_lock+0x30/0xd8

As far as I can see, this mutex only protects mmio accesses.

Is it preferable to mark the gpio chip can_sleep over replacing the
mutex with a non-sleep lock?

> [    9.233749]  lpi_config_set+0x2e8/0x3c8 [pinctrl_lpass_lpi]
> [    9.233757]  lpi_gpio_direction_output+0x58/0x90 [pinctrl_lpass_lpi]
> [    9.233761]  gpiod_direction_output_raw_commit+0x110/0x428
> [    9.233772]  gpiod_direction_output_nonotify+0x234/0x358
> [    9.233779]  gpiod_direction_output+0x38/0xd0
> [    9.233786]  gpio_shared_proxy_direction_output+0xb8/0x2a8 [gpio_shared_proxy]
> [    9.233792]  gpiod_direction_output_raw_commit+0x110/0x428
> [    9.233799]  gpiod_direction_output_nonotify+0x234/0x358
> [    9.233806]  gpiod_configure_flags+0x2c0/0x580
> [    9.233812]  gpiod_find_and_request+0x358/0x4f8
> [    9.233819]  gpiod_get_index+0x7c/0x98
> [    9.233826]  devm_gpiod_get+0x34/0xb0
> [    9.233829]  reset_gpio_probe+0x58/0x128 [reset_gpio]
> [    9.233836]  auxiliary_bus_probe+0xb0/0xf0
> [    9.233845]  really_probe+0x14c/0x450
> [    9.233853]  __driver_probe_device+0xb0/0x188
> [    9.233858]  driver_probe_device+0x4c/0x250
> [    9.233863]  __driver_attach+0xf8/0x2a0
> [    9.233868]  bus_for_each_dev+0xf8/0x158
> [    9.233872]  driver_attach+0x30/0x48
> [    9.233876]  bus_add_driver+0x158/0x2b8
> [    9.233880]  driver_register+0x74/0x118
> [    9.233886]  __auxiliary_driver_register+0x94/0xe8
> [    9.233893]  init_module+0x34/0xfd0 [reset_gpio]
> [    9.233898]  do_one_initcall+0xec/0x300
> [    9.233903]  do_init_module+0x64/0x260
> [    9.233910]  load_module+0x16c4/0x1900
> [    9.233915]  __arm64_sys_finit_module+0x24c/0x378
> [    9.233919]  invoke_syscall+0x4c/0xe8
> [    9.233925]  el0_svc_common+0x8c/0xf0
> [    9.233929]  do_el0_svc+0x28/0x40
> [    9.233934]  el0_svc+0x38/0x100
> [    9.233938]  el0t_64_sync_handler+0x84/0x130
> [    9.233943]  el0t_64_sync+0x17c/0x180
> 
> Mark the controller as sleeping.
> 
> Fixes: 6e261d1090d6 ("pinctrl: qcom: Add sm8250 lpass lpi pinctrl driver")
> Cc: stable@vger.kernel.org
> Reported-by: Val Packett <val@packett.cool>
> Closes: https://lore.kernel.org/all/98c0f185-b0e0-49ea-896c-f3972dd011ca@packett.cool/
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

If we stick to the mutex, the patch LGTM 

Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Regards,
Bjorn

> ---
>  drivers/pinctrl/qcom/pinctrl-lpass-lpi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
> index 1c97ec44aa5ff..78212f9928430 100644
> --- a/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
> +++ b/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c
> @@ -498,7 +498,7 @@ int lpi_pinctrl_probe(struct platform_device *pdev)
>  	pctrl->chip.base = -1;
>  	pctrl->chip.ngpio = data->npins;
>  	pctrl->chip.label = dev_name(dev);
> -	pctrl->chip.can_sleep = false;
> +	pctrl->chip.can_sleep = true;
>  
>  	mutex_init(&pctrl->lock);
>  
> -- 
> 2.51.0
>
Re: [PATCH] pinctrl: qcom: lpass-lpi: mark the GPIO controller as sleeping
Posted by Bartosz Golaszewski 5 days, 7 hours ago 
On Wed, Nov 26, 2025 at 3:35 PM Bjorn Andersson <andersson@kernel.org> wrote:
>
> On Wed, Nov 26, 2025 at 01:22:19PM +0100, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > The gpio_chip settings in this driver say the controller can't sleep
> > but it actually uses a mutex for synchronization. This triggers the
> > following BUG():
> >
> > [    9.233659] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281
> > [    9.233665] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 554, name: (udev-worker)
> > [    9.233669] preempt_count: 1, expected: 0
> > [    9.233673] RCU nest depth: 0, expected: 0
> > [    9.233688] Tainted: [W]=WARN
> > [    9.233690] Hardware name: Dell Inc. Latitude 7455/0FK7MX, BIOS 2.10.1 05/20/2025
> > [    9.233694] Call trace:
> > [    9.233696]  show_stack+0x24/0x38 (C)
> > [    9.233709]  dump_stack_lvl+0x40/0x88
> > [    9.233716]  dump_stack+0x18/0x24
> > [    9.233722]  __might_resched+0x148/0x160
> > [    9.233731]  __might_sleep+0x38/0x98
> > [    9.233736]  mutex_lock+0x30/0xd8
>
> As far as I can see, this mutex only protects mmio accesses.
>
> Is it preferable to mark the gpio chip can_sleep over replacing the
> mutex with a non-sleep lock?
>

I'd say let's do this as a fix and convert the driver to non-sleeping
with a spinlock next cycle?

Bart

> >
> > Mark the controller as sleeping.
> >
> > Fixes: 6e261d1090d6 ("pinctrl: qcom: Add sm8250 lpass lpi pinctrl driver")
> > Cc: stable@vger.kernel.org
> > Reported-by: Val Packett <val@packett.cool>
> > Closes: https://lore.kernel.org/all/98c0f185-b0e0-49ea-896c-f3972dd011ca@packett.cool/
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> If we stick to the mutex, the patch LGTM
>
> Reviewed-by: Bjorn Andersson <andersson@kernel.org>
>

Patchew 2.1-devel-b67e4c2

© 2016 - 2025 Red Hat, Inc.