Comment 9 for bug 1847361

Just theorizing for now ...

For a packaging solution we would need:
- qemu-block-extra / qemu-system-gui binary packages would need
  sort of a -$buildid in the name. That could be the version
  string (sanitized for package name)
- /usr/lib/x86_64-linux-gnu/qemu/*.so would need a -$buildid
- loading of modules from qemu would need to consider $buildid
  when creating module names.
  util/module.c in module_load_one / module_load_file
  It already searches in multiple dirs, maybe it could insert
  the $buildid there
- We'd need a way of detecting running versions of qemu binaries
  and only make them uninstallable once the binaries are all
  gone. I have not seen something like that in apt yet (kernel
  is easy in comparison as only one can be loaded at a time).

ALTERNATIVES:
- disable loadable module support
- add an option to load all modules in advance (unlikely to be
  liked upstream) and not desirable for many setups using qemu
  (especially not as default)
- add an option to load a module (e.g via QMP/HMP) which would
  allow an admin
  to decide doing so for the few setups that benefit.
  - that could down the road then even get a libvirt interface
    for easier consumption

Heads up - None of the above would be SRUable