adduser Pre-Depends for qemu-system-common
qemu-system-common installs a udev rules file which sets /dev/kvm group
to 'kvm'. Its postinst then adds a kvm group. However udev reads the
new rules file as soon as it sees it, sees that group kvm doesn't
exist, and ignores that part of the rule (until reboot, udev restart,
or the rule is re-added, of course).
To fix this the kvm group should be created during preinst before the
udev rules file is unpacked. This requires adding adduser to the
Pre-Depends. vorlon warned me that any new pre-depends should be
discussed here first, so I'm emailing to ask - is this ok? Is there
a better way?