From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] KVM: Move KVM context switch into own function
Date: Wed, 20 Oct 2010 18:20:41 +0200
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Cc: Andi Kleen <andi@firstfloor.org>, mtosatti@redhat.com,
	kvm@vger.kernel.org, Andi Kleen <ak@linux.intel.com>
To: Avi Kivity <avi@redhat.com>
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On Wed, Oct 20, 2010 at 06:12:11PM +0200, Avi Kivity wrote:
>  On 10/20/2010 05:56 PM, Andi Kleen wrote:
> >From: Andi Kleen<ak@linux.intel.com>
> >
> >gcc 4.5 with some special options is able to duplicate the VMX
> >context switch asm in vmx_vcpu_run(). This results in a compile error
> >because the inline asm sequence uses an on local label. The non local
> >label is needed because other code wants to set up the return address.
> >
> 
> Curious, any idea why gcc does that?  I guess it's the unlikely()
> near the top.

Don't know why, i wasn't motivated to go through its debugging dumps
for this. But strictly the problem could always happen,
not even a "volatile" stops that.

-Andi