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Date: Sat, 20 Apr 2002 12:30:02 -0700 (PDT)
From: Linus Torvalds <torvalds@transmeta.com>
To: Andrea Arcangeli <andrea@suse.de>
cc: Brian Gerst <bgerst@didntduck.org>, "H. Peter Anvin" <hpa@zytor.com>,
        <ak@suse.de>, <linux-kernel@vger.kernel.org>, <jh@suse.cz>
Subject: Re: [PATCH] Re: SSE related security hole
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On Sat, 20 Apr 2002, Andrea Arcangeli wrote:
> 
> Well, my preferred patch is still this one :)

But this one simply will not get applied, for all the reasons already
outlined. It _will_ cause the same problems that it tries to fix, just at
some later time.

Besides, I seriously doubt it is any faster than what is there already.

Time it, and notice how:

 - fninit takes about 200 cycles
 - fxrstor takes about 215 cycles

and your added 16*(pxor/xorps) likely takes at least 8 cycles.

In short, your "fast" code isn't actually any faster than doing it right.

		Linus

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