[libvirt] unable to start guest under kvm (revisited)

The problem, that I post here http://www.mail-archive.com/libvir-list@redhat.com/msg16154.html and that was solved, comes back in a different way. Consider a working kvm machine with the following description: ... <os> <type arch='x86_64' machine='pc'>hvm</type> <boot dev='hd'/> </os> ... If I delete "machine='pc'" attribute from <type>, so description becomes ... <os> <type arch='x86_64'>hvm</type> <boot dev='hd'/> </os> ... then libvirt chooses a machine='pc-0.11' value (again: qemu API version instead of kvm version) and I get virsh # start DD error: Failed to start domain DD error: internal error unable to start guest: Supported machines are: pc Standard PC (default) isapc ISA-only PC --- This problem actually occurs when using virt-manager, see https://www.redhat.com/archives/virt-tools-list/2009-October/msg00037.html