If the user space is frozen, we cannot wait for it to complete.

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

Signed-off-by: Ricardo Ribalda ribalda@chromium.org --- To: Jaroslav Kysela perex@perex.cz To: Takashi Iwai tiwai@suse.com Cc: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" joel@joelfernandes.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/core/init.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)

diff --git a/sound/core/init.c b/sound/core/init.c index 5377f94eb211..35fb71177fea 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -9,6 +9,7 @@ #include <linux/module.h> #include <linux/device.h> #include <linux/file.h> +#include <linux/freezer.h> #include <linux/slab.h> #include <linux/time.h> #include <linux/ctype.h> @@ -573,6 +574,13 @@ void snd_card_disconnect_sync(struct snd_card *card) return; }

+#ifdef CONFIG_FREEZER + if (pm_freezing) { + dev_err(card->dev, "Userspace is frozen, skipping sync\n"); + return; + } +#endif + spin_lock_irq(&card->files_lock); wait_event_lock_irq(card->remove_sleep, list_empty(&card->files_list), @@ -658,6 +666,15 @@ int snd_card_free(struct snd_card *card) ret = snd_card_free_when_closed(card); if (ret) return ret; + +#ifdef CONFIG_FREEZER + /* + * If userspace is frozen the wait from completion will never end. + */ + if (pm_freezing) + return 0; +#endif + /* wait, until all devices are ready for the free operation */ wait_for_completion(&released);

--- base-commit: 4312098baf37ee17a8350725e6e0d0e8590252d4 change-id: 20221127-snd-freeze-1ee143228326

Best regards,