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Date: Mon, 15 Aug 2011 09:12:07 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Andrew Lutomirski <luto@mit.edu>
CC: Borislav Petkov <bp@alien8.de>, melwyn lobo <linux.melwyn@gmail.com>,
        Denys Vlasenko <vda.linux@googlemail.com>, Ingo Molnar <mingo@elte.hu>,
        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>, borislav.petkov@amd.com
Subject: Re: x86 memcpy performance
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On 08/15/2011 08:36 AM, Andrew Lutomirski wrote:
> 
> (*)  kernel_fpu_begin is a bad name.  It's only safe to use integer
> instructions inside a kernel_fpu_begin section because MXCSR (and the
> 387 equivalent) could contain garbage.
> 

Uh... no, it just means you have to initialize the settings.  It's a
perfectly good name, it's called kernel_fpu_begin, not kernel_fp_begin.

	-hpa