Message-ID: <48678BBF.80707@qumranet.com>
Date: Sun, 29 Jun 2008 16:18:55 +0300
From: Avi Kivity <avi@qumranet.com>
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To: Andi Kleen <andi@firstfloor.org>
CC: Agner Fog <agner@agner.org>, Arjan van de Ven <arjan@infradead.org>,
       "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org
Subject: Re: ABI change for device drivers using future AVX instruction set
References: <48626514.2040905@agner.org> <20080625092224.736c2541@infradead.org> <4862ECAB.1040402@zytor.com> <4864CFA5.9050901@agner.org> <20080627072231.7337ba18@infradead.org> <4865F0DA.2050906@agner.org> <87myl5pyqo.fsf@basil.nowhere.org> <4866541F.1060709@agner.org> <20080628200231.GA21259@one.firstfloor.org> <48677313.8000804@qumranet.com> <48677E39.6000001@firstfloor.org> <486780BA.6010202@qumranet.com> <486788F4.5060202@firstfloor.org>
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Andi Kleen wrote:
>>>> We could change kernel_fpu_begin() not to disable
>>>> preemption, but instead set a task flag.  When we get the "no device"
>>>> fault, if the flag is set, save the fpu state into the kernel fpu save
>>>> area     
>>>>         
>>> What kernel fpu save area do you mean?
>>>   
>>>       
>> A new one, of course.
>>
>>     
>
> With that we would be eventually in the mess Agner talked about.
>
>   

If you use xsave, I don't see how this is different to the user fpu save 
area.

-- 
error compiling committee.c: too many arguments to function

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