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>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
* call suspend and power-down; used both from PM and power-save
* this function returns the power state in the end
*/
* call suspend and power-down; used both from PM and power-save
* this function returns the power state in the end
*/
-static unsigned int hda_call_codec_suspend(struct hda_codec *codec)
+static unsigned int hda_call_codec_suspend(struct hda_codec *codec, bool in_wq)
codec->patch_ops.suspend(codec);
hda_cleanup_all_streams(codec);
state = hda_set_power_state(codec, AC_PWRST_D3);
codec->patch_ops.suspend(codec);
hda_cleanup_all_streams(codec);
state = hda_set_power_state(codec, AC_PWRST_D3);
- 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);
spin_lock(&codec->power_lock);
snd_hda_update_power_acct(codec);
trace_hda_power_down(codec);
}
spin_unlock(&codec->power_lock);
}
spin_unlock(&codec->power_lock);
- state = hda_call_codec_suspend(codec);
+ state = hda_call_codec_suspend(codec, true);
codec->pm_down_notified = 0;
if (!bus->power_keep_link_on && (state & AC_PWRST_CLK_STOP_OK)) {
codec->pm_down_notified = 1;
codec->pm_down_notified = 0;
if (!bus->power_keep_link_on && (state & AC_PWRST_CLK_STOP_OK)) {
codec->pm_down_notified = 1;
list_for_each_entry(codec, &bus->codec_list, list) {
if (hda_codec_is_power_on(codec))
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);