Re: [libvirt] guests and pulseaudio fighting over audio devices
On Tue, Sep 15, 2009 at 04:45:31PM -0400, Dave Allan wrote:
I noticed that when a KVM guest created with virt-manager is running
on
F10, sound on the physical host stops working. When all VMs are
shutdown, sound starts working again. Removing the <sound> tag from the
VM XML allows sound to work while the VM is booted. To further
complicate troubleshooting, if audio is already playing when the guest
is started it keeps playing, since pulse already has the device open.
The message in /var/log/messages when I try to play audio is:
pulseaudio[6492]: module-alsa-sink.c: Error opening PCM device front:0:
Device or resource busy
strace of pulseaudio shows:
open("/dev/snd/pcmC0D0p", O_RDWR|O_NONBLOCK) = -1 EBUSY (Device or
resource busy)
but fuser and lsof show nothing. A trivial test program also sees
Device or resource busy when trying to open /dev/snd/pcmC0D0p
I am in favor of removing the <sound> tag from the default
configuration, since I don't use sound from within guests and I do use
sound on my desktop, but perhaps this behavior is specific to my
configuration. I haven't investigated it exhaustively. What does
everybody else think?
It is complicated :-) In Fedora >= 11 we currently disable all use of
sound cards, but this upsets people who want sound ;-P I'm working
on a new version of the patch which sets up audio-over-VNC, while for
SDL allows the host audio backend to be used & configured.
I still need to finish my GTK-VNC patches to do the client end of
audio over VNC, then it'll all play correctly with desktop audio
services via gstreamer/pulseaudio
Daniel
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