On Fri, 15 Jul 2022 21:29:09 +0800
Zheyu Ma <zheyuma97@xxxxxxxxx> wrote:
> The driver uses managed resource API to register the iio device, so it
> is unnecessarg to unregister the device manually.
>
> 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@xxxxxxxxx>
Unfortunately the fix still leaves the release order as not mirroring the ordering
in probe. As such, I think the right fix is to not use devm_iio_device_register()
but rather use the non managed form.
Thanks,
Jonathan
> ---
> drivers/iio/light/isl29028.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/iio/light/isl29028.c b/drivers/iio/light/isl29028.c
> index 9de3262aa688..505235903bd8 100644
> --- a/drivers/iio/light/isl29028.c
> +++ b/drivers/iio/light/isl29028.c
> @@ -641,8 +641,6 @@ static int isl29028_remove(struct i2c_client *client)
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
> struct isl29028_chip *chip = iio_priv(indio_dev);
>
> - iio_device_unregister(indio_dev);
> -
> pm_runtime_disable(&client->dev);
> pm_runtime_set_suspended(&client->dev);
>
