From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH] x86: KVM, fix lock imbalance
Date: Wed, 7 Jul 2010 16:10:08 +0200
Message-ID: <20100707141008.GA7419@elte.hu>
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 <4C347C0E.6020107@gmail.com>
 <4C347F3C.2010704@redhat.com>
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Cc: Jiri Slaby <jirislaby@gmail.com>, linux-kernel@vger.kernel.org,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	"H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
	Gleb Natapov <gleb@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Gregory Haskins <ghaskins@novell.com>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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* Avi Kivity <avi@redhat.com> wrote:

> On 07/07/2010 04:07 PM, Jiri Slaby wrote:
> >
> >>A cleanliness comment: why is that tear-down/dealloc sequence open-coded? It
> >>should be at the end of the function, with goto labels, like we do it in
> >>similar cases.
> >Because the lock is around a block only. I usually don't create a goto
> >fail-paths in these cases. Do you want one?
> 
> In any case, the patch is a minimal fix, so I'll apply it.  Any clean ups 
> can go on top.

The reason the pattern caught my attention is that it is one of the typical 
cases where goto labels help prevent similar bugs. I.e. had it been clean to 
begin with the bug might not have happened.

Thanks,

	Ingo