[PATCH 5.1 036/115] ASoC: soc-core: fixup references at soc_cleanup_card_resources()

From: Greg Kroah-Hartman
Date: Mon Jun 17 2019 - 17:24:57 EST


From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>

commit 29040d1ac569606fece70966179de272cfc0d4db upstream.

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@xxxxxxxxxxxxxxx # for v5.1
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/soc/soc-core.c | 7 ++++++-
sound/soc/soc-dapm.c | 3 +++
2 files changed, 9 insertions(+), 1 deletion(-)

--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -228,7 +228,10 @@ static void soc_init_card_debugfs(struct

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 sn
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);
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -2192,7 +2192,10 @@ static void dapm_debugfs_add_widget(stru

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