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From: Juan Quintela <quintela@redhat.com>
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	(Peter Maydell's message of "Wed, 19 Nov 2014 14:10:36 +0000")
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Date: Wed, 19 Nov 2014 15:18:01 +0100
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Subject: Re: [Qemu-devel] [PATCH 2/5] exec: qemu_ram_alloc_device,
	qemu_ram_resize
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>

Peter Maydell <peter.maydell@linaro.org> wrote:
> On 19 November 2014 14:07, Juan Quintela <quintela@redhat.com> wrote:
>> My understanding is that it is a "trick".  We have internal memory for a
>> device that is needed for the emulation, but not showed to the guest.
>> And it is big enough that we want to save it during the "live" stage of
>> migration, so we mark it as RAM.  if it is somekind of cash, we can just
>> enlarge it on destination, and it don't matter.  If this has anything
>> different on the other part of the RAM, we are on trouble.
>
> Would it be feasible to just have the migration code provide
> an API for registering things to be migrated in the live
> migration stage, rather than creating memory regions which
> you can't actually use for most of the purposes the memory
> region API exists for?

If somebody told me what they need, we can do it.

Stefan, you needed something like that for data-plane?  Or that memory
is mapped on the guest?

Later, Juan.