From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@qumranet.com>
Subject: Re: [PATCH] x86_emulate: Emulate nop (0x90) instruction
Date: Sat, 14 Jun 2008 18:26:22 +0300
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Cc: Mohammed Gamal <m.gamal005@gmail.com>, kvm@vger.kernel.org,
	riel@surriel.com
To: Andi Kleen <andi@firstfloor.org>
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Andi Kleen wrote:
>> Thanks for pointing this out. 0x90 is also the opcode for xchg r8,rAX
>> instruction.
>>     
>
> But nop doesn't actually need to execute exchange.
>   

The sequence 0x41 0x90 uses the 0x90 opcode but is not a nop.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.