On 03/13/18 22:23, Andy Shevchenko wrote:
> On Tue, Mar 13, 2018 at 9:34 PM, Kirill Marinushkin
> <k.marinush...@gmail.com> wrote:
>> In the current implementation, `rmmod snd_bcm2835` does not release
>> resources properly. It causes an oops when trying to list sound devices.
>>
>> This commit fixes it.
> Nice catch!
>
> See my comments below.
>
>> static void snd_devm_unregister_child(struct device *dev, void *res)
>> {
>> struct device *childdev = *(struct device **)res;
>> + struct bcm2835_chip *chip = dev_get_drvdata(childdev);
>> + struct snd_card *card = chip->card;
>> +
>> + snd_card_free(card);
>> + dev_set_drvdata(childdev, NULL);
> AFAIU this is done by device core.
Maybe you are right. But I don't know, which function in the device core does
it.
It is safe to have this line. So, I suggest to keep it.
>
>> device_unregister(childdev);
>> }
>> +static void snd_devm_release(struct device *dev)
>> +{
>> + struct bcm2835_chip *chip = dev_get_drvdata(dev);
>> +
>> + kfree(chip);
>> +}
>
>> /* chip-specific constructor
>> @@ -122,7 +136,7 @@ static int snd_bcm2835_create(struct snd_card *card,
>>
>> err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
>> if (err) {
>> - snd_bcm2835_free(chip);
>> + kfree(chip);
> Do you call device_register() inside snd_device_new()?
> In this case you might need put_device() here instead of simple kfree().
No, from what I see, device_register() does not happen inside snd_device_new().
>> return err;
>> }
