On my machine, a guest fails to boot if it has a sound card, but not
graphical device/display is configured, because pulseaudio fails to
initialize since it can't access $HOME.
A workaround is removing the audio device, however on ARM boards there
isn't any option to do that, so -nographic always fails.
Set QEMU_AUDIO_DRV=none if no <graphics> are configured. Unfortunately
this has massive test suite fallout.
Add a qemu.conf parameter nographics_allow_host_audio, that if enabled
will pass through QEMU_AUDIO_DRV from sysconfig (similar to
vnc_allow_host_audio)
<hyperv>
<spinlocks state='off'/>
</hyperv>
results in:
error: XML error: missing HyperV spinlock retry count
Don't require retries when state is off and use virXPathUInt
instead of virXPathString to simplify parsing.
https://bugzilla.redhat.com/show_bug.cgi?id=784836#c19
