From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 2/3] x86_64: Define 128-bit memory-mapped I/O operations
Date: Tue, 21 Aug 2012 18:37:24 -0700
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Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, netdev@vger.kernel.org,
	linux-net-drivers@solarflare.com, x86@kernel.org
To: Ben Hutchings <bhutchings@solarflare.com>
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On 08/21/2012 06:23 PM, Ben Hutchings wrote:
> Define reado(), writeo() and their raw counterparts using SSE.
> 
> Based on work by Stuart Hodgson <smhodgson@solarflare.com>.

It would be vastly better if we explicitly controlled this with
kernel_fpu_begin()/kernel_fpu_end() rather than hiding it in primitives
than might tempt the user to do very much the wrong thing.

Also, it needs to be extremely clear to the user that these operations
use the FPU, and all the requirements there need to be met, including
not using them at interrupt time.

	-hpa