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Date: Mon, 10 Nov 2014 20:34:54 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20141110183454.GA17883@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH for-2.2] pc: acpi: mark all possible CPUs
 as enabled in SRAT
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>, qemu-devel@nongnu.org

On Mon, Nov 10, 2014 at 07:26:41PM +0100, Paolo Bonzini wrote:
> 
> 
> On 10/11/2014 19:17, Michael S. Tsirkin wrote:
> > > No, I mean can you do it also for pc-2.1 and earlier?  Or should it be
> > > only for the last machine type?
> > 
> > I don't see why it should, it can't break migration.
> > 
> 
> It changes the contents of the SRAT.  There is a possibility that it
> triggers bugs in previously working guests.
> 
> Paolo

Absolutely but that's true for any bugfix.
We don't do compatiblity without a good reason.

Or do you mean that you consider this too high a risk for 2.2?

-- 
MST