Kvm driver : loosen qemu-kvm -M option

Hello,

I am not able to migrate from hypervisor A to hypervisor B but I can from B to A … servers are the same hardware, under centos, the only difference is that A is centos 6.5 and B is centos 6.6. I have compared everything to my knowledge and that’s the only difference I can find.

On machine A: /usr/libexec/qemu-kvm -M ?
Supported machines are:
pc RHEL 6.5.0 PC (alias of rhel6.5.0)
rhel6.5.0 RHEL 6.5.0 PC (default)
rhel6.4.0 RHEL 6.4.0 PC

On machine B:
/usr/libexec/qemu-kvm -M ?
Supported machines are:
pc RHEL 6.6.0 PC (alias of rhel6.6.0)
rhel6.6.0 RHEL 6.6.0 PC (default)
rhel6.5.0 RHEL 6.5.0 PC
rhel6.4.0 RHEL 6.4.0 PC

Is there any way to 'edit machine A to add rhel6.6 or to force qemu-kvm to accept any machine?