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Date:   Tue, 12 Sep 2023 12:18:04 +0200
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Peter Ujfalusi" <peter.ujfalusi@linux.intel.com>, tiwai@suse.com,
        "Jaroslav Kysela" <perex@perex.cz>
Cc:     "Masahiro Yamada" <masahiroy@kernel.org>,
        linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org
Subject: Re: [PATCH] ALSA: core: Increase the name array size for debugfs directory
 name
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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);
 #endif
        return 0;
 

   Arnd