From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <5102D688.6080901@siemens.com>
Date: Fri, 25 Jan 2013 20:01:28 +0100
From: Jan Kiszka <jan.kiszka@siemens.com>
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Subject: Re: [Xenomai] Lacking xsave support in Xenomai
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai <xenomai@xenomai.org>

On 2013-01-25 19:44, Gilles Chanteperdrix wrote:
> On 01/25/2013 03:06 PM, Jan Kiszka wrote:
> 
>> Hi all,
>>
>> yesterday I pushed a fix to my for-upstream queue that properly disables
>> all xsave-dependent CPU features (AVX/AVX2 namely). However, this is no
>> real solution for us as it blocks a lot of acceleration potential on
>> current Intel CPUs.
>>
>> Did anyone already look into this in more details? Is it just a matter
>> of implementing the necessary context switching bits? Are there known
> 
>> pitfalls?
> 
> The known pitfalls of FPU support is that we never get it right the
> first time. And debugging why it fails is hard.

OK, so no conceptual issues. And it will remain controllable via "noxsave".

Still need to discuss details here, but I bet we will look into this soon.

Thanks,
Jan

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