[alsa-devel] [PATCH] ASoC: soc-core: fixup references at soc_cleanup_card_resources()

[Kuninori Morimoto]

From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>

commit 53e947a0e1f7 ("ASoC: soc-core: merge card resources cleanup
method") merged cleanup method of snd_soc_instantiate_card() and
soc_cleanup_card_resources().

But, after this commit, if user uses unbind/bind to Component factor
drivers, Kernel might indicates refcount error at
soc_cleanup_card_resources().

The 1st reason is card->snd_card is still exist even though
snd_card_free() was called, but it is already cleaned.
We need to set NULL to it.

2nd is card->dapm and card create debugfs, but its dentry is still
exist even though it was removed. We need to set NULL to it.

Fixes: 53e947a0e1f7 ("ASoC: soc-core: merge card resources cleanup method")
Cc: stable at vger.kernel.org # for v5.1
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
 sound/soc/soc-core.c | 7 ++++++-
 sound/soc/soc-dapm.c | 3 +++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 46e3ab0..758159a 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -228,7 +228,10 @@ static void soc_init_card_debugfs(struct snd_soc_card *card)
 
 static void soc_cleanup_card_debugfs(struct snd_soc_card *card)
 {
+	if (!card->debugfs_card_root)
+		return;
 	debugfs_remove_recursive(card->debugfs_card_root);
+	card->debugfs_card_root = NULL;
 }
 
 static void snd_soc_debugfs_init(void)
@@ -2034,8 +2037,10 @@ static void soc_check_tplg_fes(struct snd_soc_card *card)
 static int soc_cleanup_card_resources(struct snd_soc_card *card)
 {
 	/* free the ALSA card at first; this syncs with pending operations */
-	if (card->snd_card)
+	if (card->snd_card) {
 		snd_card_free(card->snd_card);
+		card->snd_card = NULL;
+	}
 
 	/* remove and free each DAI */
 	soc_remove_dai_links(card);
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 0382a47..5d9d767 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -2192,7 +2192,10 @@ static void dapm_debugfs_add_widget(struct snd_soc_dapm_widget *w)
 
 static void dapm_debugfs_cleanup(struct snd_soc_dapm_context *dapm)
 {
+	if (!dapm->debugfs_dapm)
+		return;
 	debugfs_remove_recursive(dapm->debugfs_dapm);
+	dapm->debugfs_dapm = NULL;
 }
 
 #else
-- 
2.7.4