Re: USB sound card freezes USB after resume from suspend

[Takashi Iwai <tiwai@suse.de>]

On Tue, 25 Apr 2023 20:19:24 +0200,
Jakub Kicinski wrote:
> 
> Hi!
> 
> For a few weeks now I can't use any USB devices if I suspend my laptop
> with my USB sound card active and resuming it without it connected.
> 
> USB worker threads seems to be sitting in:
> 
> [<0>] snd_pcm_dev_disconnect+0x1e8/0x280 [snd_pcm]
> [<0>] snd_device_disconnect_all+0x42/0x80 [snd]
> [<0>] snd_card_disconnect+0x128/0x290 [snd]
> [<0>] usb_audio_disconnect+0x11a/0x2c0 [snd_usb_audio]
> [<0>] usb_unbind_interface+0x8c/0x270
> [<0>] device_release_driver_internal+0x1b2/0x230
> [<0>] bus_remove_device+0xd8/0x150
> [<0>] device_del+0x18b/0x410
> [<0>] usb_disable_device+0xc6/0x1e0
> [<0>] usb_disconnect+0xda/0x2c0
> [<0>] usb_disconnect+0xbf/0x2c0
> [<0>] usb_disconnect+0xbf/0x2c0
> [<0>] usb_disconnect+0xbf/0x2c0
> [<0>] hub_event+0xf01/0x1cd0
> [<0>] process_one_work+0x1c4/0x3d0
> [<0>] worker_thread+0x4d/0x380
> [<0>] kthread+0xe6/0x110
> [<0>] ret_from_fork+0x29/0x50
> 
> Which is:
> 
> snd_pcm_dev_disconnect (/usr/src/debug/kernel-6.2.12/linux-6.2.12-300.fc38.x86_64/sound/core/pcm.c:818 /usr/src/debug/kernel-6.2.12/linux-6.2.12-300.fc38.x86_64/sound/core/pcm.c:812 /usr/src/debug/kernel-6.2.12/linux-6.2.12-300.fc38.x86_64/sound/core/pcm.c:1129) snd_pcm
> 
> It happens on Fedora 37 and Fedora 38, it seems to have coincided with
> the 6.2 kernel but I'm not 100% sure.
> 
> The USB devices come back after half an hour or so, silently.
> There's nothing of note in dmesg.

AFAIK, there has been no similar report, so far.

Is it a regression?  If yes, could you figure out which kernel version
starts showing the problem (or at best bisection)?


thanks,

Takashi