On 14.08.2013, at 20:27, Peter Maydell wrote: > On 14 August 2013 19:21, Alexander Graf <ag...@suse.de> wrote: >> Everything -cpu host does has to be reproducible without -cpu host, > > This is in general not going to be possible (the obvious case > being "QEMU doesn't know about the host CPU type at all", or > in minor variants "QEMU knows about the host CPU type but QEMU's > version has a slightly different feature set").
That's a shortcoming in that particular version of QEMU then. The KVM interface still allows to do everything you could do with -cpu host with an explicit CPU define. If user space wants, it could write away the host CPU type and try to live migrate that machine to another machine then with the explicit target vcpu id. Please keep in mind that we're talking about the generic KVM / user space interface here, not the actual QEMU implementation. Alex
