On Jul 29, 2011, at 5:25 PM, Mauro Carvalho Chehab wrote:
> Em 29-07-2011 14:30, Jarod Wilson escreveu:
>> On Jul 29, 2011, at 1:53 AM, Mauro Carvalho Chehab wrote:
>>
>>> rc unregister logic were deadly broken, preventing some drivers to
>>> be removed. Among the broken things, rc_dev_uevent() is being called
>>> during device_del(), causing a data filling on an area that it is
>>> not ready anymore.
>>>
>>> Also, some drivers have a stop callback defined, that needs to be called
>>> before data removal, as it stops data polling.
>>>
>>> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
>>>
>>> diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
>>> index 51a23f4..666d4bb 100644
>>> --- a/drivers/media/rc/rc-main.c
>>> +++ b/drivers/media/rc/rc-main.c
>>> @@ -928,10 +928,6 @@ out:
>>>
>>> static void rc_dev_release(struct device *device)
>>> {
>>> - struct rc_dev *dev = to_rc_dev(device);
>>> -
>>> - kfree(dev);
>>> - module_put(THIS_MODULE);
>>> }
>>
>> Since this function become a no-op, does it make sense to just remove it
>> and not set a .release function for static struct device_type rc_dev_type?
>
> As you tested, this function needs to exist... well, other drivers sometimes
> do the same, by defining it as a no-op function.
>
>> Other than that, after reading through the patch several times, along with
>> the resulting rc-main.c and some input code, everything seems to make
>> sense to me. Will do some quick sanity-testing with a few of my various
>> devices before I give an ack though, just to be sure. :)
>
> Thanks! Yeah, a test with other devices is welcome, as we don't want fix for one
> and break for the others ;)
Done. Checked out mceusb, redrat3 and imon, all show no ill effects.
> The logic there looks simple, but it is, in fact, tricky, especially since
> drivers may have polling tasks running, and they need to be cancelled before
> freeing the resources.
Indeed. Took a bit to wrap my head around it all, but I think I got it.
Acked-by: Jarod Wilson <jarod@xxxxxxxxxx>
--
Jarod Wilson
jarod@xxxxxxxxxxxx
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