Re: [PATCH v2] media: i2c: vd56g3: clean up subdev state on probe failure

[Benjamin Mugnier <benjamin.mugnier@foss.st.com>]

Hi Sakari,

Le 18/06/2026 à 13:53, Sakari Ailus a écrit :
> Hi Benjamin,
> 
> On Tue, Jun 16, 2026 at 02:49:54PM +0200, Benjamin Mugnier wrote:
>> Hi,
>>
>> Thank you for your patch, and apologies for the delay.
>>
>> Le 24/04/2026 à 18:52, Myeonghun Pak a écrit :
>>> vd56g3_subdev_init() calls v4l2_subdev_init_finalize(), which allocates
>>> the subdev active state and requires v4l2_subdev_cleanup() to release it.
>>>
>>> If vd56g3_update_controls() fails after finalize succeeds, the probe error
>>> path currently skips v4l2_subdev_cleanup() and returns an error. The driver
>>> .remove() callback is not called after a failed probe, so the active state
>>> is leaked.
>>>
>>> Route this error through a subdev cleanup label before freeing the control
>>> handler and media entity.
>>>
>>> Fixes: 87aa97fc3157 ("media: i2c: Add driver for ST VD56G3 camera sensor")
>>> Cc: stable@vger.kernel.org
>>> Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
>>> ---
>>> Changes in v2:
>>> - Use a lowercase subject summary.
>>
>> Please keep the first character uppercase, just like other commits on
>> this module.
>>
>>>
>>>  drivers/media/i2c/vd56g3.c | 5 ++++-
>>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/media/i2c/vd56g3.c b/drivers/media/i2c/vd56g3.c
>>> index 157acea9e2..43f792288a 100644
>>> --- a/drivers/media/i2c/vd56g3.c
>>> +++ b/drivers/media/i2c/vd56g3.c
>>> @@ -1427,11 +1427,14 @@ static int vd56g3_subdev_init(struct vd56g3 *sensor)
>>>  	v4l2_subdev_unlock_state(state);
>>>  	if (ret) {
>>>  		dev_err(sensor->dev, "Controls update failed: %d\n", ret);
>>> -		goto err_ctrls;
>>> +		goto err_subdev;
>>>  	}
>>>  
>>>  	return 0;
>>>  
>>> +err_subdev:
>>> +	v4l2_subdev_cleanup(&sensor->sd);
>>
>> v4l2_subdev_cleanup() is already performed in the caller (i.e.
>> vd56g3_probe()), but as you noticed it is not called from this path. I'd
>> rather have the return value route correctly through
>> v4l2_subdev_cleanup() in  vd56g3_probe(), allowing to keep a unique call
>> to v4l2_subdev_cleanup() instead.
> 
> Is it?
> 
> If vd56g3_update_controls() in vd56g3_subdev_init() fails, it'll jump to
> err_power_off in vd56g3_probe() which does PM related cleanup only.
> 

Exactly, I realize my sentence was poorly written, but if I understand
correctly we're on the same page. The problem being
v4l2_subdev_cleanup() not being called in any path if
vd56g3_update_controls() fails.

Now if vd56g3_update_controls() fails, instead of performing
v4l2_subdev_cleanup() in vd56g3_subdev_init() as this patch does, I'd
rather have it done in vd56g3_probe()'s jump back so we can keep it all
at the same place, instead of having 2 v4l2_subdev_cleanup() in 2
different places.

Tell me if this is still unclear.

>>
>> This patch looks like is LLM generated and sparks my curiosity. If so
>> you must disclaim it using an Assisted-by tag [1]. Sorry if I’m mistaken.
>>
>> [1] https://docs.kernel.org/process/coding-assistants.html
>>
>>> +
>>>  err_ctrls:
>>>  	v4l2_ctrl_handler_free(sensor->sd.ctrl_handler);
>>>  
>>
>> -- 
>> Regards,
>> Benjamin
>>
> 

-- 
Regards,
Benjamin