[Qemu-devel] Re: [PATCH v4] savevm: Fix no_migrate

[Alex Williamson <alex.williamson@redhat.com>]

On Mon, 2011-01-10 at 10:24 +0000, Daniel P. Berrange wrote:
> On Fri, Jan 07, 2011 at 03:13:25PM -0700, Alex Williamson wrote:
> > The no_migrate save state flag is currently only checked in the
> > last phase of migration.  This means that we potentially waste
> > a lot of time and bandwidth with the live state handlers before
> > we ever check the no_migrate flags.  The error message printed
> > when we catch a non-migratable device doesn't get printed for
> > a detached migration.  And, no_migrate does nothing to prevent
> > an incoming migration to a target that includes a non-migratable
> > device.  This attempts to fix all of these.
> > 
> > One notable difference in behavior is that an outgoing migration
> > now checks for non-migratable devices before ever connecting to
> > the target system.  This means the target will remain listening
> > rather than exit from failure.
> > 
> > Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> > ---
> > 
> > v4:
> >   - fix braces noted by Jan
> >   - return error from qemu_savevm_state_blocked rather than fixed EINVAL
> >     at qemu_loadvm_state(), since it'a already using errno values
> > 
> > v3:
> > 
> > Daniel, adding you to see if libvirt cares about the difference in
> > whether the target exits on migration failure as noted above.
> 
> If the 'migrate' command on the source QEMU returns an error,
> then libvirt will teardown the target QEMU automatically, so
> that's not a problem.

Thanks, that's the way I was hoping it would work.

Alex