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Date: Sun, 30 Apr 2006 16:59:49 +0800
From: David Xu <davidxu@freebsd.org>
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To: Igor Sysoev <is@rambler-co.ru>
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Cc: freebsd-current@freebsd.org
Subject: Re: FreeBSD-SA-06:14.fpu
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Igor Sysoev wrote:
> 
> The last security advisory FreeBSD-SA-06:14.fpu
> ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-06:14.fpu.asc
> that fixes very doubtful security bug in AMD CPUs, also
> adds unnecessary penalty in FPU context switch for all other
> SSE-enabled CPUs.
> 
> 
> Igor Sysoev
> http://sysoev.ru/en/

Probably it should only be applied to AMD CPU but not Intel and others,
it is easy to check cpu vendor and put a
if (bug_fxsave)
	fpu_clean_state();

in file npx.c.

David Xu