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Date: Thu, 26 Jan 2017 16:53:07 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Rik van Riel <riel@redhat.com>
Cc: linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>, Borislav Petkov <bp@alien8.de>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Yu-cheng Yu <yu-cheng.yu@intel.com>
Subject: Re: [PATCH 5/7] x86/fpu: Change fpu->fpregs_active users to
 fpu->fpstate_active
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* Rik van Riel <riel@redhat.com> wrote:

> Let me go totally reimplement this whole project in a different way...

Note that I can still be convinced about complicating the FPU state machine as 
well if that ends up being the best approach for KVM - but it appears to me (from 
a very superficial look) that turning vCPU threads into no-FPU kthreads or 
representing the guest FPU state directly with the host FPU context would be even 
more beneficial, from the simplicity and KVM performance POV?

> At least I found some good FPU bugs and cleanups along the way.

Absolutely, and your efforts are much appreciated! This ptrace state handling 
madness that bit you on SkyLake was something I missed entirely.

Thanks,

	Ingo