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Date: Sun, 21 Apr 2002 04:09:42 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@suse.de>, Linus Torvalds <torvalds@transmeta.com>,
        Brian Gerst <bgerst@didntduck.org>, linux-kernel@vger.kernel.org,
        jh@suse.cz
Subject: Re: [PATCH] Re: SSE related security hole
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On Sat, Apr 20, 2002 at 03:43:17PM -0700, H. Peter Anvin wrote:
> Andrea Arcangeli wrote:
> >
> >As said in an earlier email it is a matter of memory bandwith, 59 bytes
> >of icache and zero data, against 7 bytes of icache and 512bytes of data.
> >the 512bytes of data are visibly slower, period. Saving mem bandwith is
> >much more important than reducing the number of instructions, even more
> >on SMP!
> >
> 
> It's not 512 bytes of data -- only the part that's actually used is 
> accessed.

On current x86 yes (so far), but the x86-64 the whole 512bytes will have
to be read from ram instead.

Andrea
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