[PATCH v5] ASoC: SOF: Fix deadlock when shutdown a frozen userspace
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@vger.kernel.org Fixes: 83bfc7e793b5 ("ASoC: SOF: core: unregister clients and machine drivers in .shutdown") Signed-off-by: Ricardo Ribalda ribalda@chromium.org --- To: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com To: Liam Girdwood lgirdwood@gmail.com To: Peter Ujfalusi peter.ujfalusi@linux.intel.com To: Bard Liao yung-chuan.liao@linux.intel.com To: Ranjani Sridharan ranjani.sridharan@linux.intel.com To: Kai Vehmanen kai.vehmanen@linux.intel.com To: Daniel Baluta daniel.baluta@nxp.com To: Mark Brown broonie@kernel.org To: Jaroslav Kysela perex@perex.cz To: Takashi Iwai tiwai@suse.com Cc: sound-open-firmware@alsa-project.org Cc: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org --- Changes in v5: - Edit subject prefix - Link to v4: https://lore.kernel.org/r/20221127-snd-freeze-v4-0-51ca64b7f2ab@chromium.org
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@chromium.org
Changes in v3: - Wrap pm_freezing in a function - Link to v2: https://lore.kernel.org/r/20221127-snd-freeze-v2-0-d8a425ea9663@chromium.org
Changes in v2: - Only use pm_freezing if CONFIG_FREEZER - Link to v1: https://lore.kernel.org/r/20221127-snd-freeze-v1-0-57461a366ec2@chromium.org --- 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,
Hi,
On Mon, 28 Nov 2022, Ricardo Ribalda wrote:
During kexec(), the userspace is frozen. Therefore we cannot wait for it to complete.
Avoid running snd_sof_machine_unregister during shutdown.
[...]
/*
* 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.
- snd_sof_machine_unregister(sdev, pdata);
- if (sdev->fw_state == SOF_FW_BOOT_COMPLETE)
this is problematic as removing that machine_unregister() call will (at least) bring back an issue on Intel platforms (rare problem hitting S5 on Chromebooks).
Not sure how to solve this, but if that call needs to be removed (unsafe to call at shutdown), then we need to rework how SOF does the cleanup.
Br, Kai
Hi Kay
Thanks for your review
On Mon, 28 Nov 2022 at 15:41, Kai Vehmanen kai.vehmanen@linux.intel.com wrote:
Hi,
On Mon, 28 Nov 2022, Ricardo Ribalda wrote:
During kexec(), the userspace is frozen. Therefore we cannot wait for it to complete.
Avoid running snd_sof_machine_unregister during shutdown.
[...]
/*
* 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)this is problematic as removing that machine_unregister() call will (at least) bring back an issue on Intel platforms (rare problem hitting S5 on Chromebooks).
Do you know which devices were affected or how to trigger the issue?
I have access to the ChromeOS lab, so I can test on a big variety of devices
Thanks!
Not sure how to solve this, but if that call needs to be removed (unsafe to call at shutdown), then we need to rework how SOF does the cleanup.
Br, Kai
participants (2)
-
Kai Vehmanen -
Ricardo Ribalda