Re: [Qemu-devel] [PATCH 1/1] s390x/migration: Introduce 2.4 machine

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Wed,  1 Jul 2015 11:16:57 +0200
Christian Borntraeger <borntraeger@de.ibm.com> wrote:

> The section footer changes commit f68945d42bab ("Add a protective
> section footer") and commit 37fb569c0198 ("Disable section footers
> on older machine types") broke migration for any non-versioned
> machines.
> 
> While one can argue that section footer should be enabled
> explicitely for new versions instead of disabled for old ones,
> this pinpoints to a problem of s390-ccw-machines: it needs to
> be versioned to be compatible with future changes in common
> code data structures such as section footers.
> 
> Let's introduce a version scheme for s390-ccw-virtio machines.
> We will use the old s390-ccw-virtio name as alias to the latest
> version as all existing libvirt XML for the ccw type were expanded
> by libvirt to that name.
> 
> The only downside of this patch is, that the old alias s390-ccw
> will no longer be available as machines can have only one alias,
> but it should not really matter.
> 
> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Cc: Juan Quintela <quintela@redhat.com>
> Cc: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
> Cc: Jason J. Herne <jjherne@linux.vnet.ibm.com>
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> ---
>  hw/s390x/s390-virtio-ccw.c | 22 ++++++++++++++++++----
>  1 file changed, 18 insertions(+), 4 deletions(-)

Adapted the commit message and applied (with minor tweaks) to my
s390-next branch at

git://github.com/cohuck/qemu s390-next

I'll probably send a pull request including this patch tomorrow, unless
someone has further comments.