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Date: Tue, 31 Jul 2012 22:06:50 +0200
From: Michal Hocko <mhocko@suse.cz>
Subject: Re: [PATCH -alternative] mm: hugetlbfs: Close race during teardown
 of hugetlbfs shared page tables V2 (resend)
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To: Larry Woodman <lwoodman@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>, Rik van Riel <riel@redhat.com>, Hugh Dickins <hughd@google.com>, Linux-MM <linux-mm@kvack.org>, David Gibson <david@gibson.dropbear.id.au>, Ken Chen <kenchen@google.com>, Cong Wang <xiyou.wangcong@gmail.com>, LKML <linux-kernel@vger.kernel.org>

On Tue 31-07-12 13:49:21, Larry Woodman wrote:
> On 07/31/2012 08:46 AM, Mel Gorman wrote:
> >
> >Fundamentally I think the problem is that we are not correctly detecting
> >that page table sharing took place during huge_pte_alloc(). This patch is
> >longer and makes an API change but if I'm right, it addresses the underlying
> >problem. The first VM_MAYSHARE patch is still necessary but would you mind
> >testing this on top please?
> Hi Mel, yes this does work just fine.  It ran for hours without a panic so
> I'll Ack this one if you send it to the list.

Hi Larry, thanks for testing! I have a different patch which tries to
address this very same issue. I am not saying it is better or that it
should be merged instead of Mel's one but I would be really happy if you
could give it a try. We can discuss (dis)advantages of both approaches
later.

Thanks!
---