From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Mackerras <paulus@samba.org>
Subject: Re: [PATCH v5 0/8] In-kernel XICS interrupt controller emulation
Date: Sat, 27 Apr 2013 09:52:47 +1000
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Cc: Alexander Graf <agraf@suse.de>, kvm@vger.kernel.org,
	kvm-ppc@vger.kernel.org
To: Scott Wood <scottwood@freescale.com>
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On Fri, Apr 26, 2013 at 12:13:33PM -0500, Scott Wood wrote:

> Also please note that we no longer hold kvm->lock during device
> creation, so your EEXIST check looks racy.

Huh?  Patch 2/8 adds this code:

+       mutex_lock(&kvm->lock);
+       if (kvm->arch.xics)
+               ret = -EEXIST;
+       else
+               kvm->arch.xics = xics;
+       mutex_unlock(&kvm->lock);

How is that racy?

Paul.