From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 2/2] KVM: PPC: Book3S: Call into C interrupt handlers
Date: Fri, 27 Apr 2012 08:58:59 +1000
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Cc: Alexander Graf <agraf@suse.de>, kvm list <kvm@vger.kernel.org>,
	kvm-ppc <kvm-ppc@vger.kernel.org>
To: Scott Wood <scottwood@freescale.com>
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On Thu, 2012-04-26 at 16:54 -0500, Scott Wood wrote:
> On 04/26/2012 05:19 AM, Alexander Graf wrote:
> > +     asm("mfmsr %0" : "=r"(msr));
> 
> Why not just mfmsr()?
> 
> > +     asm("bl 1f; 1: mflr %0" : "=r"(ip));
> 
> You'll want to tell the compiler that you're trashing LR. 

We probably also want to make sure TRAP is set properly. Some interrupts
(like perf) will test it.

Cheers,
Ben.