This reverts commit f51424872760 ("ASoC: fsl_xcvr: fix missing lock in
fsl_xcvr_mode_put()").
The original patch attempted to acquire the card->controls_rwsem lock in
fsl_xcvr_mode_put(). However, this function is called from the upper ALSA
core function snd_ctl_elem_write(), which already holds the write lock on
controls_rwsem for the whole put operation. So there is no need to simply
hold the lock for fsl_xcvr_activate_ctl() again.
Acquiring the read lock while holding the write lock in the same thread
results in a deadlock and a hung task, as reported by Alexander Stein.
Reported-by: Alexander Stein <[email protected]>
Closes: https://lore.kernel.org/linux-sound/5056506.GXAFRqVoOG@steina-w/
Signed-off-by: Ziyi Guo <[email protected]>
---
v2:
- Refactor subject line style
- Include human readable descriptions
- Fix the sha1 information for sound/soc/fsl/fsl_xcvr.c
sound/soc/fsl/fsl_xcvr.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/sound/soc/fsl/fsl_xcvr.c b/sound/soc/fsl/fsl_xcvr.c
index 5de93f458b56..a268fb81a2f8 100644
--- a/sound/soc/fsl/fsl_xcvr.c
+++ b/sound/soc/fsl/fsl_xcvr.c
@@ -223,13 +223,10 @@ static int fsl_xcvr_mode_put(struct snd_kcontrol
*kcontrol,
xcvr->mode = snd_soc_enum_item_to_val(e, item[0]);
- down_read(&card->snd_card->controls_rwsem);
fsl_xcvr_activate_ctl(dai, fsl_xcvr_arc_mode_kctl.name,
(xcvr->mode == FSL_XCVR_MODE_ARC));
fsl_xcvr_activate_ctl(dai, fsl_xcvr_earc_capds_kctl.name,
(xcvr->mode == FSL_XCVR_MODE_EARC));
- up_read(&card->snd_card->controls_rwsem);
-
/* Allow playback for SPDIF only */
rtd = snd_soc_get_pcm_runtime(card, card->dai_link);
rtd->pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count =
--
2.34.1
