On 08/06/17 11:02, Stefan Hajnoczi wrote: > > Please make sure your qemu-block-extra and qemu-system-x86 packages are > up-to-date. They should both have the same version number. > > Are you using a backports package for QEMU? > Thanks, something along the lines of this does seem to have been the problem. I am using the backports package but it seems that the update uprevved qemu.* modulo qemu-system-x86. After a bit of fiddling I've got it working again by updating qemu-system-x86 and then forcing the user/group in /etc/libvirt/qemu.conf (presumably the conf file was over-written by the update). David
