diff options
| author | Dylan Reid <dgreid@chromium.org> | 2012-09-28 15:57:01 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-13 05:50:33 +0900 |
| commit | 22e22876160b6b19e4aa52d8e562149840945e9b (patch) | |
| tree | d28ca9af95676140633f191ea2fe8674c2cdb206 /sound | |
| parent | 93bfa6e4dade09e6b92a84990f479c3d59a69e14 (diff) | |
ALSA: hda - Fix hang caused by race during suspend.
commit d17344b3547669f5b6ee4fda993d03737a141bd6 upstream.
There was a race condition when the system suspends while hda_power_work
is running in the work queue. If system suspend (snd_hda_suspend)
happens after the work queue releases power_lock but before it calls
hda_call_codec_suspend, codec_suspend runs with power_on=0, causing the
codec to power up for register reads, and hanging when it calls
cancel_delayed_work_sync from the running work queue.
The call chain from the work queue will look like this:
hda_power_work <<- power_on = 1, unlock, then power_on cleard by suspend
hda_call_codec_suspend
hda_set_power_state
snd_hda_codec_read
codec_exec_verb
snd_hda_power_up
snd_hda_power_save
__snd_hda_power_up
cancel_delayed_work_sync <<-- cancelling executing wq
Fix this by waiting for the work queue to finish before starting suspend
if suspend is not happening on the work queue.
Signed-off-by: Dylan Reid <dgreid@chromium.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/pci/hda/hda_codec.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index 1c65cc5e3a31..38fdefc9b0ee 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -3580,7 +3580,7 @@ static inline void hda_exec_init_verbs(struct hda_codec *codec) {} /* * call suspend and power-down; used both from PM and power-save */ -static void hda_call_codec_suspend(struct hda_codec *codec) +static void hda_call_codec_suspend(struct hda_codec *codec, bool in_wq) { if (codec->patch_ops.suspend) codec->patch_ops.suspend(codec); @@ -3589,7 +3589,9 @@ static void hda_call_codec_suspend(struct hda_codec *codec) codec->afg ? codec->afg : codec->mfg, AC_PWRST_D3); #ifdef CONFIG_SND_HDA_POWER_SAVE - cancel_delayed_work(&codec->power_work); + /* Cancel delayed work if we aren't currently running from it. */ + if (!in_wq) + cancel_delayed_work_sync(&codec->power_work); spin_lock(&codec->power_lock); snd_hda_update_power_acct(codec); trace_hda_power_down(codec); @@ -4410,7 +4412,7 @@ static void hda_power_work(struct work_struct *work) } spin_unlock(&codec->power_lock); - hda_call_codec_suspend(codec); + hda_call_codec_suspend(codec, true); if (bus->ops.pm_notify) bus->ops.pm_notify(bus); } @@ -5076,7 +5078,7 @@ int snd_hda_suspend(struct hda_bus *bus) list_for_each_entry(codec, &bus->codec_list, list) { if (hda_codec_is_power_on(codec)) - hda_call_codec_suspend(codec); + hda_call_codec_suspend(codec, false); } return 0; } |