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Date: Thu, 15 Jan 2015 12:52:22 -0600
From: Wei Huang <wei@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] arm: define version-based machine type for
	ARM
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>



On 01/15/2015 12:10 PM, Peter Maydell wrote:
> On 15 January 2015 at 17:50, Wei Huang <wei@redhat.com> wrote:
>> ARM virt machine type (machvirt) had been stable for a while. But recently
>> new devices have been added to support extra features. Considerring the
>> support of long-term compatibility, it is time to create a version-based
>> machine types.
>>
>> This patch defines a qemu 2.2 specific machine type (machvirt-2.2) and
>> points the default machvirt to it. In the future new machine types can
>> follow a similar naming scheme (e.g. machvirt-3.0, ...). Note that this
>> patch doesn't change the semantic of existing QEMU command line.
> 
> I don't think we're anywhere ready yet to support between
> version migration compatibility. We will want this *eventually*
> but we are a long long way away from needing it...(maybe a
> year?)
Thanks, Peter. I think migration support is getting closer than one
year. It might not create problems at the beginning. So I understand
your point.

-Wei

> 
> thanks
> -- PMM
>