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Date: Fri, 27 May 2016 13:30:00 -0700
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm: check the return value of lookup_page_ext for all
 call sites
Message-Id: <20160527133000.84a887b7ce8d2e6387145b4d@linux-foundation.org>
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To: "Shi, Yang" <yang.shi@linaro.org>
Cc: Minchan Kim <minchan@kernel.org>, iamjoonsoo.kim@lge.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linaro-kernel@lists.linaro.org

On Fri, 27 May 2016 13:17:19 -0700 "Shi, Yang" <yang.shi@linaro.org> wrote:

> >> Actually, I think the #ifdef should be removed if lookup_page_ext() is
> >> possible to return NULL. It sounds not make sense returning NULL only
> >> when DEBUG_VM is enabled. It should return NULL no matter what debug
> >> config is selected. If Joonsoo agrees with me I'm going to come up with
> >> a patch to fix it.
> >>
> >
> > I've lost the plot here.  What is the status of this patch?
> >
> > Latest version:
> 
> Yes, this is the latest version. We are discussing about some future 
> optimization.
> 
> And, Minchan Kim pointed out a possible race condition which exists even 
> before this patch. I proposed a quick fix, as long as they are happy to 
> the fix, I will post it to the mailing list.

OK, thanks - I've moved it into the for-Linus-next-week queue.

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