Re: [Qemu-devel] [PATCH] balloon: Fix failure of updating guest memory status

[Li, Liang Z]

> > +    if (s->stats_vq_elem == NULL) {
> > +        virtqueue_push(s->svq, &elem, 0);
> > +        virtio_notify(vdev, s->svq);
> > +        return;
> > +    }
> >      virtqueue_push(s->svq, s->stats_vq_elem, s->stats_vq_offset);
> >      virtio_notify(vdev, s->svq);
> >      g_free(s->stats_vq_elem);
> >
> 
> Hi, the right fix is to migrate s->stats_vq_elem if it is not NULL.  See how 
> it's
> done in hw/char/virtio-serial.c's virtio_serial_save_device
> (save) and fetch_active_ports_list (load).
> 
> Paolo

Hi Paolo,

   If we try to migrate ' migrate s->stats_vq_elem ', how to make it works with 
the old version ?
   with a new feature bit? Or with some version control?
   
Thanks!
Liang