[PATCH v2] iio: light: isl29028: Fix the warning in isl29028_remove()

[PATCH v2] iio: light: isl29028: Fix the warning in isl29028_remove()

[Zheyu Ma]

The driver use the non-managed form of the register function in
isl29028_remove(). To keep the release order as mirroring the ordering
in probe, the driver should use non-managed form in probe, too.

The following log reveals it:

[   32.374955] isl29028 0-0010: remove
[   32.376861] general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
[   32.377676] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
[   32.379432] RIP: 0010:kernfs_find_and_get_ns+0x28/0xe0
[   32.385461] Call Trace:
[   32.385807]  sysfs_unmerge_group+0x59/0x110
[   32.386110]  dpm_sysfs_remove+0x58/0xc0
[   32.386391]  device_del+0x296/0xe50
[   32.386959]  cdev_device_del+0x1d/0xd0
[   32.387231]  devm_iio_device_unreg+0x27/0xb0
[   32.387542]  devres_release_group+0x319/0x3d0
[   32.388162]  i2c_device_remove+0x93/0x1f0

Fixes: 2db5054ac28d ("staging: iio: isl29028: add runtime power management support")
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
---
Changes in v2:
    - Use the non-managed form to register the device
---
 drivers/iio/light/isl29028.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/isl29028.c b/drivers/iio/light/isl29028.c
index 9de3262aa688..a62787f5d5e7 100644
--- a/drivers/iio/light/isl29028.c
+++ b/drivers/iio/light/isl29028.c
@@ -625,7 +625,7 @@ static int isl29028_probe(struct i2c_client *client,
 					 ISL29028_POWER_OFF_DELAY_MS);
 	pm_runtime_use_autosuspend(&client->dev);
 
-	ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
+	ret = iio_device_register(indio_dev);
 	if (ret < 0) {
 		dev_err(&client->dev,
 			"%s(): iio registration failed with error %d\n",
-- 
2.25.1

Re: [PATCH v2] iio: light: isl29028: Fix the warning in isl29028_remove()

[Jonathan Cameron]

On Sun, 17 Jul 2022 08:42:41 +0800
Zheyu Ma <zheyuma97@gmail.com> wrote:

> The driver use the non-managed form of the register function in
> isl29028_remove(). To keep the release order as mirroring the ordering
> in probe, the driver should use non-managed form in probe, too.
> 
> The following log reveals it:
> 
> [   32.374955] isl29028 0-0010: remove
> [   32.376861] general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
> [   32.377676] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
> [   32.379432] RIP: 0010:kernfs_find_and_get_ns+0x28/0xe0
> [   32.385461] Call Trace:
> [   32.385807]  sysfs_unmerge_group+0x59/0x110
> [   32.386110]  dpm_sysfs_remove+0x58/0xc0
> [   32.386391]  device_del+0x296/0xe50
> [   32.386959]  cdev_device_del+0x1d/0xd0
> [   32.387231]  devm_iio_device_unreg+0x27/0xb0
> [   32.387542]  devres_release_group+0x319/0x3d0
> [   32.388162]  i2c_device_remove+0x93/0x1f0
> 
> Fixes: 2db5054ac28d ("staging: iio: isl29028: add runtime power management support")
> Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
As I'm doing one last pull request before the merge window, I've applied
this to the togreg branch of iio.git and marked it for stable.

Thanks,

Jonathan

> ---
> Changes in v2:
>     - Use the non-managed form to register the device
> ---
>  drivers/iio/light/isl29028.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/light/isl29028.c b/drivers/iio/light/isl29028.c
> index 9de3262aa688..a62787f5d5e7 100644
> --- a/drivers/iio/light/isl29028.c
> +++ b/drivers/iio/light/isl29028.c
> @@ -625,7 +625,7 @@ static int isl29028_probe(struct i2c_client *client,
>  					 ISL29028_POWER_OFF_DELAY_MS);
>  	pm_runtime_use_autosuspend(&client->dev);
>  
> -	ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
> +	ret = iio_device_register(indio_dev);
>  	if (ret < 0) {
>  		dev_err(&client->dev,
>  			"%s(): iio registration failed with error %d\n",