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Date: Fri, 27 Nov 2015 09:41:45 +0100
From: Ingo Molnar <mingo@kernel.org>
To: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, mingo@redhat.com, hpa@zytor.com,
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Subject: Re: irq_fpu_usable() is irreliable
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* Jason A. Donenfeld <Jason@zx2c4.com> wrote:

> Hi Ingo,
> 
> The plot thickens, once again.
> 
> > > Also, what CPU does the test system have, Intel or AMD? The FPU behavior can be
> > > very different in the two cases.
> > Intel 3820QM, but inside VMWare Workstation 12.
> 
> Trying this on bare metal, the problem goes away! Though the VM is 4.2
> and my bare metal is 4.3. Perhaps your recent changes did something.
> 
> But more likely, there's some funny business happening with VMWare.
> Any speculation about this? Fascinating issue...

I have no idea unfortunately :-( You might want to take it up with the vmware 
guys.

Thanks,

	Ingo