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Date: Sun, 21 May 2006 16:51:48 -0700 (PDT)
From: Matthew Dillon <dillon@apollo.backplane.com>
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To: David Xu <davidxu@freebsd.org>
References: <20060430142408.fcd60069.rosti.bsd@gmail.com>
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Cc: Rostislav Krasny <rosti.bsd@gmail.com>, Igor Sysoev <is@rambler-co.ru>,
	Colin Percival <cperciva@freebsd.org>, freebsd-current@freebsd.org
Subject: Re: [PATCH] FreeBSD-SA-06:14.fpu
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:>
:> By the way, following command could be used to check how kernel has
:> been compiled, regarding the CPU_FXSAVE_LEAK option:
:>
:> objdump -x /boot/kernel/kernel | grep fpu_clean_state
:
:The patch looks fine to me, but can it be CPU_FXSAVE_NOLEAK ?
:so only people know the problem will turn it on.
:
:David Xu

    I don't think it really needs to be optioned.  Since the FPU state
    is demand-loaded from a trap/exception anyway, a huge amount of code
    is run in the same path that fpu_clean_state is called from. 
    fpu_clean_state itself only eats a few nanoseconds (like maybe ~1/10
    of the time that fninit takes).

						-Matt