https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=220949
Bug ID: 220949
Summary: When the only USB soundcard is disconnected, defunct
/dev/dsp0 is left, kernel warnings, programs hang
Product: Base System
Version: 11.0-STABLE
Hardware: Any
OS: Any
Status: New
Severity: Affects Only Me
Priority: ---
Component: usb
Assignee: freebsd-usb@FreeBSD.org
Reporter: y...@rawbw.com
I have a USB webcam that is also a soundcard with only a microphone, and no
speaker. When there are no other audio devices, disconnecting this USB webcam
causes system dysfunction.
There are a lot of repeating messages in log:
> Jul 23 09:14:21 yv kernel: pcm0: unregister: mixer busy
> Jul 23 09:14:21 yv kernel: pcm0: Waiting for sound application to exit!
> Jul 23 09:14:23 yv kernel: pcm0: unregister: mixer busy
> Jul 23 09:14:23 yv kernel: pcm0: Waiting for sound application to exit!
Programs that have this device open hanged and became unkillable with kill -9.
'kldunload snd_uaudio.ko' also hangs in unkillable state.
USB is hot-pluggable. Device is supposed to disappear and reappear without any
long-term effects.
IMO, /dev/dspN should disappear when device is removed. Programs that have it
opened should behave gracefully. They should only get errors from it and not
hang.
USB webcam: HD Pro Webcam C920 (vendor 0x046d, product 0x6860)
--
You are receiving this mail because:
You are the assignee for the bug.
___
freebsd-usb@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-usb
To unsubscribe, send any mail to "freebsd-usb-unsubscr...@freebsd.org"
