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Date: Mon, 14 Dec 2009 14:18:33 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] cpuid problem in upstream qemu with kvm
References: <20091214193541.GA6150@redhat.com> <4B269596.1050103@codemonkey.ws>
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org, Gleb Natapov <gleb@redhat.com>, avi@redhat.com

Michael S. Tsirkin wrote:
> This might help 32 bit guests, but not guests with 64 bit
> kernel and 32 bit userspace (my case) because all 64 bit
> CPUs advertise syscall bit in cpuid. Thus 64 bit guests
> do not seem to even bother checking this bit:
> AMD + 64 bit -> syscall.
>   

Okay, I don't see a great option other than migrating the vendor_id string.

Otherwise, cross vendor migration will not work by default.  Maybe 
that's not a problem but if so, we really should change the default cpu 
model to be much more aggressive about exposing host features.

Regards,

Anthony Liguori