diff options
| author | Takashi Iwai <tiwai@suse.de> | 2022-01-19 16:52:49 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2022-01-28 15:59:18 +0000 |
| commit | 9f620684c1ef5a002b6622ecc7b5818e81252f48 (patch) | |
| tree | 19585edbcba394a2d9114f460f058d324956b39a /sound | |
| parent | 3c75c0ea5da749bd1efebd1387f2e5011b8c7d78 (diff) | |
| download | lwn-9f620684c1ef5a002b6622ecc7b5818e81252f48.tar.gz lwn-9f620684c1ef5a002b6622ecc7b5818e81252f48.zip | |
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 <m.szyprowski@samsung.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20220119155249.26754-3-tiwai@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/soc/soc-pcm.c | 12 |
1 files changed, 9 insertions, 3 deletions
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 */ |