On Wed, Jun 22, 2016 at 01:02:04PM +0100, Peter Maydell wrote: > On 22 June 2016 at 12:54, Dr. David Alan Gilbert <dgilb...@redhat.com> wrote: > > * Peter Maydell (peter.mayd...@linaro.org) wrote: > >> On 22 June 2016 at 12:35, Dr. David Alan Gilbert <dgilb...@redhat.com> > >> wrote: > >> > Yes, my hope is that any versioned machine type should migrate to > >> > a newer qemu with the same machine type set. > >> > > >> > There are really two separate things that we state with the machine > >> > versioning: > >> > a) that the guest view is the same > >> > b) that the migration format is the same > >> > >> Well, this is true for PC. > > > > PC, ppc/spapr, and I think s390. > > > >> But my impression when we started > >> applying versioned machine types to ARM virt was that it was > >> signing up to (a) but not (yet) (b)... > > > > So that would make ARM special; the problem is we have no way > > to communicate to the user that it's special. > > Is anybody testing that migration between versions for > virt works?
We've only tested migration between identically configured hosts so far. This is partly due to the fact that we haven't released a RHEL machine type yet, i.e. we're working towards a RHEL-7.3 machine type on a RHEL-7.3 QEMU, which will be the first and only we have. When we have a development 7.4 branch to work with then we'd test a 7.3 machine migration from a 7.3 host to a 7.4 host as well. I'll add trying an upstream 2.6 machine type migration from a 2.6 QEMU to a latest QEMU to our TODO. Thanks, drew
