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From: Andi Kleen <ak@suse.de>
To: Avi Kivity <avi@argo.co.il>
Subject: Re: FP in kernelspace
Date: Sun, 30 Jul 2006 20:15:33 +0200
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> 
> Cannot work on x86-64, even disregarding fp exceptions, because 
> kernel_fpu_begin() doesn't save the sse state which is used by fp math.
> 
> No?

It does - FXSAVE saves everything.

BTW you can use x87 on x86-64 too, you just need to use long double.

-Andi