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From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 8 Aug 2018 14:47:44 +0100
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Subject: Re: [Qemu-devel] [PATCH] migration: Correctly handle subsections
 with no 'needed' function
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To: Juan Quintela <quintela@redhat.com>
Cc: QEMU Developers <qemu-devel@nongnu.org>, "patches@linaro.org" <patches@linaro.org>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>

On 8 August 2018 at 08:27, Juan Quintela <quintela@redhat.com> wrote:
>
> This is part of the problem.  For some architectures, we don't even care
> about migraiton.  For others, we care about migration but not
> cross-version.  And yet in others we care very much (downstream
> specially).

I think we should care about migration on all architectures
and devices, in the sense that we want savevm/loadvm to work.
This is a really useful debugging and user tool, and when
I'm reviewing devices it's the minimum bar I think new
devices should clear. You then get migration "for free" but
I don't particularly expect it to be used compared to
snapshot save/restore. (Of course some of our existing code
doesn't support this, and we don't have a good way of testing
so bugs creep in easily, but as a principle I think it's
good.)

thanks
-- PMM