Re: [PATCH] ALSA: core: Increase the name array size for debugfs directory name

From: Péter Ujfalusi
Date: Tue Sep 12 2023 - 06:58:59 EST




On 12/09/2023 13:42, Takashi Iwai wrote:
> On Tue, 12 Sep 2023 12:18:04 +0200,
> Arnd Bergmann wrote:
>>
>> On Tue, Sep 12, 2023, at 10:39, Peter Ujfalusi wrote:
>>
>>> While the code is correct, we need to silence the compiler somehow.
>>> It could be done by limiting the range in sprintf like
>>> sprintf(name, "card%d", idx % SNDRV_CARDS);
>>> sprintf(name, "card%hhd", idx);
>>> etc
>>>
>>> These are too workaroundish. Increase the name array to 15 instead which
>>> looks better and only adds 7 bytes on stack.
>>
>> It looks like we use the same string for kobject_set_name(), so
>> maybe this would work as well:
>>
>> --- a/sound/core/init.c
>> +++ b/sound/core/init.c
>> @@ -278,9 +278,6 @@ static int snd_card_init(struct snd_card *card, struct device *parent,
>> size_t extra_size)
>> {
>> int err;
>> -#ifdef CONFIG_SND_DEBUG
>> - char name[8];
>> -#endif
>>
>> if (extra_size > 0)
>> card->private_data = (char *)card + sizeof(struct snd_card);
>> @@ -364,8 +361,8 @@ static int snd_card_init(struct snd_card *card, struct device *parent,
>> }
>>
>> #ifdef CONFIG_SND_DEBUG
>> - sprintf(name, "card%d", idx);
>> - card->debugfs_root = debugfs_create_dir(name, sound_debugfs_root);
>> + card->debugfs_root = debugfs_create_dir(kobject_name(&card->card_dev.kobj),
>> + sound_debugfs_root);
>
> The idea looks neat, but I suppose it's better with
> dev_name(&card->card_dev) instead?

Yes, this looks better, I will send a new patch in a minute.

>
> thanks,
>
> Takashi

--
Péter