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Date: Thu, 17 Sep 2015 12:47:40 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH] virtio: add some migration doc
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To: Greg Kurz <gkurz@linux.vnet.ibm.com>
Cc: jasowang@redhat.com, kraxel@redhat.com, qemu-devel@nongnu.org, mst@redhat.com

On Thu, 17 Sep 2015 12:39:31 +0200
Greg Kurz <gkurz@linux.vnet.ibm.com> wrote:
> On Thu, 17 Sep 2015 11:06:01 +0200
> Cornelia Huck <cornelia.huck@de.ibm.com> wrote:

> > +Devices need to be careful in their state processing during load: The
> > +load_device() procedure is invoked by the core before subsections have
> > +been loaded. Any code that depends on information transmitted in subsections
> > +therefore has to be invoked in the device's load() function _after_
> > +virtio_load() returned (like e.g. code depending on features).
> > +
> 
> From a VMState standpoint, such code would land in a post-load callback most of
> the time. Would that help comprehension if we introduce a virtio_post_load()
> function ?

It might. I think the main problem is that we need to do some stuff
post-load, and it's not really obvious what it is.