[PATCH v4] ALSA: core: Fix deadlock when shutdown a frozen userspace
From: Ricardo Ribalda
Date: Mon Nov 28 2022 - 08:43:26 EST
During kexec(), the userspace is frozen. Therefore we cannot wait for it
to complete.
Avoid running snd_sof_machine_unregister during shutdown.
This fixes:
[ 84.943749] Freezing user space processes ... (elapsed 0.111 seconds) done.
[ 246.784446] INFO: task kexec-lite:5123 blocked for more than 122 seconds.
[ 246.819035] Call Trace:
[ 246.821782] <TASK>
[ 246.824186] __schedule+0x5f9/0x1263
[ 246.828231] schedule+0x87/0xc5
[ 246.831779] snd_card_disconnect_sync+0xb5/0x127
...
[ 246.889249] snd_sof_device_shutdown+0xb4/0x150
[ 246.899317] pci_device_shutdown+0x37/0x61
[ 246.903990] device_shutdown+0x14c/0x1d6
[ 246.908391] kernel_kexec+0x45/0xb9
And:
[ 246.893222] INFO: task kexec-lite:4891 blocked for more than 122 seconds.
[ 246.927709] Call Trace:
[ 246.930461] <TASK>
[ 246.932819] __schedule+0x5f9/0x1263
[ 246.936855] ? fsnotify_grab_connector+0x5c/0x70
[ 246.942045] schedule+0x87/0xc5
[ 246.945567] schedule_timeout+0x49/0xf3
[ 246.949877] wait_for_completion+0x86/0xe8
[ 246.954463] snd_card_free+0x68/0x89
...
[ 247.001080] platform_device_unregister+0x12/0x35
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 83bfc7e793b5 ("ASoC: SOF: core: unregister clients and machine drivers in .shutdown")
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
To: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
To: Liam Girdwood <lgirdwood@xxxxxxxxx>
To: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>
To: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
To: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
To: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
To: Daniel Baluta <daniel.baluta@xxxxxxx>
To: Mark Brown <broonie@xxxxxxxxxx>
To: Jaroslav Kysela <perex@xxxxxxxx>
To: Takashi Iwai <tiwai@xxxxxxxx>
Cc: sound-open-firmware@xxxxxxxxxxxxxxxx
Cc: alsa-devel@xxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
Changes in v4:
- Do not call snd_sof_machine_unregister from shutdown.
- Link to v3: https://lore.kernel.org/r/20221127-snd-freeze-v3-0-a2eda731ca14@xxxxxxxxxxxx
Changes in v3:
- Wrap pm_freezing in a function
- Link to v2: https://lore.kernel.org/r/20221127-snd-freeze-v2-0-d8a425ea9663@xxxxxxxxxxxx
Changes in v2:
- Only use pm_freezing if CONFIG_FREEZER
- Link to v1: https://lore.kernel.org/r/20221127-snd-freeze-v1-0-57461a366ec2@xxxxxxxxxxxx
---
sound/soc/sof/core.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/sound/soc/sof/core.c b/sound/soc/sof/core.c
index 3e6141d03770..9616ba607ded 100644
--- a/sound/soc/sof/core.c
+++ b/sound/soc/sof/core.c
@@ -475,19 +475,16 @@ EXPORT_SYMBOL(snd_sof_device_remove);
int snd_sof_device_shutdown(struct device *dev)
{
struct snd_sof_dev *sdev = dev_get_drvdata(dev);
- struct snd_sof_pdata *pdata = sdev->pdata;
if (IS_ENABLED(CONFIG_SND_SOC_SOF_PROBE_WORK_QUEUE))
cancel_work_sync(&sdev->probe_work);
/*
- * make sure clients and machine driver(s) are unregistered to force
- * all userspace devices to be closed prior to the DSP shutdown sequence
+ * make sure clients are unregistered prior to the DSP shutdown
+ * sequence.
*/
sof_unregister_clients(sdev);
- snd_sof_machine_unregister(sdev, pdata);
-
if (sdev->fw_state == SOF_FW_BOOT_COMPLETE)
return snd_sof_shutdown(sdev);
---
base-commit: 4312098baf37ee17a8350725e6e0d0e8590252d4
change-id: 20221127-snd-freeze-1ee143228326
Best regards,
--
Ricardo Ribalda <ribalda@xxxxxxxxxxxx>