From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: ftrace/perf_event leak
Date: Wed, 01 Sep 2010 12:26:14 +0300
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Cc: Ingo Molnar <mingo@elte.hu>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	kvm-devel <kvm@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
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  On 09/01/2010 12:04 PM, Peter Zijlstra wrote:
>
> Does something like the below cure that?
>

Unfortunately not.

> I seem to remember C doesn't make any promises about the order of logic
> statements, hence we need to explicitly pull out that try_module_get()
> so that it evaluates after the rest of the conditions.

&& and || are executed in order (so you can write

    if (p && p->x)

).

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.