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Date: Mon, 14 Dec 2009 16:01:33 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] Re: [PATCH RFC] virtio: add features qdev property
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org

On 12/14/09 14:59, Michael S. Tsirkin wrote:
> It's not an easy quesiton.
> If we do it as disable bits, then we get incompatible
> machines when running on different hosts.

In case that one host supports feature which the other doesn't and the 
feature isn't masked out?  Well, management failure I'd say.  The whole 
point of the compat machine types (and properties used there) is to make 
sure the vm's are compatible even in case the hosts run different 
software versions.

cheers,
   Gerd