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Date: Fri, 19 Apr 2002 17:19:01 -0700 (PDT)
Subject: Re: [PATCH] Re: SSE related security hole
From: "H. Peter Anvin" <hpa@zytor.com>
To: <torvalds@transmeta.com>
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>
>
> On Fri, 19 Apr 2002, H. Peter Anvin wrote:
>>
>> Indeed.  Logically, FNINIT should have been extended to initialize it
>> all - - it is a security hole that it doesn't initialize MMX properly.
>
> Well, MMX should arguably be initialized with "emms", so the proper
> sequence migth be something like
>

Remember that one of the original design goals of MMX was to run on
unmodified operating systems (and it can't be turned off); thus needing
any extra initialization is a bug.

    -hpa



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