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Date: Wed, 17 Jun 2015 09:25:47 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] Migration compatibility for serial
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To: Markus Armbruster <armbru@redhat.com>
Cc: amit.shah@redhat.com, pbonzini@redhat.com, qemu-devel@nongnu.org, "Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>, quintela@redhat.com

On Wed, Jun 17, 2015 at 09:11:56AM +0200, Markus Armbruster wrote:
> "Michael S. Tsirkin" <mst@redhat.com> writes:
> 
> > On Wed, Jun 17, 2015 at 08:52:42AM +0200, Markus Armbruster wrote:
> >> "Dr. David Alan Gilbert (git)" <dgilbert@redhat.com> writes:
> >> 
> >> > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> >> >
> >> > Older QEMUs dont understand the new (sub)sections that
> >> > may be generated in the serial device.   Limit their generation
> >> > to newer machine types.
> >> 
> >> Please explain briefly what state migration can lose with old machine
> >> types, and how this could impact the guest.  The commits adding the
> >> subsections should have the information[*].  Pointers to them might
> >> suffice.
> >> 
> >> 
> >> [*] Should != do; I didn't check.
> >
> > OTOH if we have flags named after specific portions we skip,
> > and not after qemu versions, this becomes evident from code.
> 
> The commit message needs to spell things out regardless.

Sure, thanks for pointing this out.