From 9f620684c1ef5a002b6622ecc7b5818e81252f48 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 19 Jan 2022 16:52:49 +0100 Subject: ASoC: soc-pcm: Move debugfs removal out of spinlock The recent fix for DPCM locking also covered the loop in dpcm_be_disconnect() with the FE stream lock. This caused an unexpected side effect, thought: calling debugfs_remove_recursive() in the spinlock may lead to lockdep splats as the code there assumes the SOFTIRQ-safe context. For avoiding the problem, this patch changes the disconnection procedure to two phases: at first, the matching entries are removed from the linked list, then the resources are freed outside the lock. Fixes: b7898396f4bb ("ASoC: soc-pcm: Fix and cleanup DPCM locking") Reported-and-tested-by: Marek Szyprowski Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20220119155249.26754-3-tiwai@suse.de Signed-off-by: Mark Brown --- sound/soc/soc-pcm.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'sound') diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index e8876e65c649..9a954680d492 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -1268,6 +1268,7 @@ static void dpcm_be_reparent(struct snd_soc_pcm_runtime *fe, void dpcm_be_disconnect(struct snd_soc_pcm_runtime *fe, int stream) { struct snd_soc_dpcm *dpcm, *d; + LIST_HEAD(deleted_dpcms); snd_soc_dpcm_mutex_assert_held(fe); @@ -1287,13 +1288,18 @@ void dpcm_be_disconnect(struct snd_soc_pcm_runtime *fe, int stream) /* BEs still alive need new FE */ dpcm_be_reparent(fe, dpcm->be, stream); - dpcm_remove_debugfs_state(dpcm); - list_del(&dpcm->list_be); + list_move(&dpcm->list_fe, &deleted_dpcms); + } + snd_soc_dpcm_stream_unlock_irq(fe, stream); + + while (!list_empty(&deleted_dpcms)) { + dpcm = list_first_entry(&deleted_dpcms, struct snd_soc_dpcm, + list_fe); list_del(&dpcm->list_fe); + dpcm_remove_debugfs_state(dpcm); kfree(dpcm); } - snd_soc_dpcm_stream_unlock_irq(fe, stream); } /* get BE for DAI widget and stream */ -- cgit v1.2.3