[PATCH AUTOSEL 5.4 13/30] ASoC: SOF: Intel: hda-dai: fix potential locking issue

From: Sasha Levin
Date: Tue Nov 09 2021 - 17:37:10 EST


From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>

[ Upstream commit a20f3b10de61add5e14b6ce4df982f4df2a4cbbc ]

The initial hdac_stream code was adapted a third time with the same
locking issues. Move the spin_lock outside the loops and make sure the
fields are protected on read/write.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Acked-by: Mark Brown <broonie@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210924192417.169243-5-pierre-louis.bossart@xxxxxxxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/soc/sof/intel/hda-dai.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/sound/soc/sof/intel/hda-dai.c b/sound/soc/sof/intel/hda-dai.c
index 3f645200d3a5c..b3cdd10c83ae1 100644
--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -67,6 +67,7 @@ static struct hdac_ext_stream *
return NULL;
}

+ spin_lock_irq(&bus->reg_lock);
list_for_each_entry(stream, &bus->stream_list, list) {
struct hdac_ext_stream *hstream =
stream_to_hdac_ext_stream(stream);
@@ -106,12 +107,12 @@ static struct hdac_ext_stream *
* is updated in snd_hdac_ext_stream_decouple().
*/
if (!res->decoupled)
- snd_hdac_ext_stream_decouple(bus, res, true);
- spin_lock_irq(&bus->reg_lock);
+ snd_hdac_ext_stream_decouple_locked(bus, res, true);
+
res->link_locked = 1;
res->link_substream = substream;
- spin_unlock_irq(&bus->reg_lock);
}
+ spin_unlock_irq(&bus->reg_lock);

return res;
}
--
2.33.0