Subject: Re: Bug: fio traps into kernel without exiting because futex has a
	deadloop
From: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>, Darren Hart <dvhltc@us.ibm.com>,
       Rusty Russell <rusty@rustcorp.com.au>,
       LKML <linux-kernel@vger.kernel.org>
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Date: Tue, 16 Jun 2009 11:16:35 +0800
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On Mon, 2009-06-15 at 09:57 +0200, Thomas Gleixner wrote:
> On Mon, 15 Jun 2009, Zhang, Yanmin wrote:
> > > +	ret = get_user_pages_fast(addr, 1, 1, &page);
> >
> > I checked function ﻿get_user_pages_fast. It might return negative, 0, or
> > positive value. 0 means it doesn't pin any page. So why does below statement
> > use (!ret) to put_page?
> 
> Hmm, darn. You are right. It needs to be (ret > 0)
I tested (ret > 0). It does work and I didn't find memory leak.


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