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Date: Tue, 15 Dec 2009 19:56:50 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] cpuid problem in upstream qemu with kvm
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: qemu-devel@nongnu.org, Gleb Natapov <gleb@redhat.com>, avi@redhat.com

On Tue, Dec 15, 2009 at 11:37:34AM -0600, Anthony Liguori wrote:
> Michael S. Tsirkin wrote:
>> I don't think it does: cpuid is an unpriveledged operation,
>> is it not?
>>   
>
> We (qemu) ask the kernel (kvm.ko) to filter out the features bits from  
> the cpuid we expose to the guest in order to remove feature bits it  
> (kvm.ko) does not support.
>
> Regards,
>
> Anthony Liguori

I see.
But unfortunately this bit has multiple meanings
for 64/32 bit, kvm does not know whether you will
run a 32 bit or a 64 bit program.
This is a cpu architecture bug.



-- 
MST