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ASoC: soc-core: call snd_soc_unbind_card() under mutex_lock;

commit 34ac3c3eb8 ("ASoC: core: lock client_mutex while removing
link components") added mutex_lock() at soc_remove_link_components().

Is is called from snd_soc_unbind_card()

	snd_soc_unbind_card()
=>		soc_remove_link_components()
		soc_cleanup_card_resources()
			soc_remove_dai_links()
=>				soc_remove_link_components()

And, there are 2 way to call it.

(1)
	snd_soc_unregister_component()
**		mutex_lock()
			snd_soc_component_del_unlocked()
=>				snd_soc_unbind_card()
**		mutex_unlock()

(2)
	snd_soc_unregister_card()
=>		snd_soc_unbind_card()

(1) case is already using mutex_lock() when it calles
snd_soc_unbind_card(), thus, we will get lockdep warning.

commit 495f926c68 ("ASoC: core: Fix deadlock in
snd_soc_instantiate_card()") tried to fixup it, but still not
enough. We still have lockdep warning when we try unbind/bind.

We need mutex_lock() under snd_soc_unregister_card()
instead of snd_remove_link_components()/snd_soc_unbind_card().

Fixes: 34ac3c3eb8 ("ASoC: core: lock client_mutex while removing link components")
Fixes: 495f926c68 ("ASoC: core: Fix deadlock in snd_soc_instantiate_card()")
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
alistair/sunxi64-5.4-dsi
Kuninori Morimoto 2019-06-19 10:07:19 +09:00 committed by Mark Brown
parent 281c443f1e
commit b545542a0b
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GPG Key ID: 24D68B725D5487D0
1 changed files with 2 additions and 2 deletions

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@ -2837,14 +2837,12 @@ static void snd_soc_unbind_card(struct snd_soc_card *card, bool unregister)
snd_soc_dapm_shutdown(card);
snd_soc_flush_all_delayed_work(card);
mutex_lock(&client_mutex);
/* remove all components used by DAI links on this card */
for_each_comp_order(order) {
for_each_card_rtds(card, rtd) {
soc_remove_link_components(card, rtd, order);
}
}
mutex_unlock(&client_mutex);
soc_cleanup_card_resources(card);
if (!unregister)
@ -2863,7 +2861,9 @@ static void snd_soc_unbind_card(struct snd_soc_card *card, bool unregister)
*/
int snd_soc_unregister_card(struct snd_soc_card *card)
{
mutex_lock(&client_mutex);
snd_soc_unbind_card(card, true);
mutex_unlock(&client_mutex);
dev_dbg(card->dev, "ASoC: Unregistered card '%s'\n", card->name);
return 0;