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Date: Wed, 06 Jan 2010 16:48:38 +0200
From: Dor Laor <dlaor@redhat.com>
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Subject: Re: [Qemu-devel] cpuid problem in upstream qemu with kvm
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To: Avi Kivity <avi@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, John Cooper <john.cooper@redhat.com>, qemu-devel@nongnu.org, Alexander Graf <agraf@suse.de>

On 01/06/2010 04:32 PM, Avi Kivity wrote:
> On 01/06/2010 04:22 PM, Michael S. Tsirkin wrote:
>>> We can probably default -enable-kvm to -cpu host, as long as we explain
>>> very carefully that if users wish to preserve cpu features across
>>> upgrades, they can't depend on the default.
>> Hardware upgrades or software upgrades?
>
> Yes.
>

I just want to remind all the the main motivation for using -cpu 
realModelThatWasOnceShiped is to provide correct cpu emulation for the 
guest. Using a random qemu|kvm64+flag1-flag2 might really cause trouble 
for the guest OS or guest apps.

On top of -cpu nehalem we can always add fancy features like x2apic, etc.