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Date: Wed, 14 Sep 2005 13:46:58 -0500
From: Anthony Liguori <aliguori@us.ibm.com>
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Subject: Re: [Qemu-devel] About qemu emulation speed (a question) and	supported
	OS
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To: qemu-devel@nongnu.org

Jim C. Brown wrote:

>On Tue, Sep 13, 2005 at 11:27:39PM -0500, Anthony Liguori wrote:
>  
>
>>I reckon kqemu has this same problem... Technically, even in ring 3, if 
>>you run natively, you violate the Popek/Goldberg requirements because of 
>>cpuid.  It's just not possible to trap it but it shouldn't matter for 
>>most software.
>>
>>    
>>
>
>It is possible to trap it, in a sense. You just read ahead and replace the
>cpuid instruction with something else.
>  
>
You can't readahead beyond a basic block.  Taking a trap for each basic 
block and translating the block is what QEMU does.

Regards,

Anthony Liguori

>Ugly, but doable.
>
>  
>