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Date: Fri, 20 Jun 2014 15:32:40 -0500 (CDT)
From: Christoph Lameter <cl@gentwo.org>
To: Hugh Dickins <hughd@google.com>
cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Naoya Horiguchi <nao.horiguchi@gmail.com>
Subject: Re: kernel BUG at /src/linux-dev/mm/mempolicy.c:1738! on v3.16-rc1
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References: <20140619215641.GA9792@nhori.bos.redhat.com> <alpine.DEB.2.11.1406200923220.10271@gentwo.org> <20140620194639.GA30729@nhori.bos.redhat.com> <alpine.LSU.2.11.1406201257370.8123@eggly.anvils>
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On Fri, 20 Jun 2014, Hugh Dickins wrote:

> [PATCH] mm: fix crashes from mbind() merging vmas
>
> v2.6.34's 9d8cebd4bcd7 ("mm: fix mbind vma merge problem") introduced
> vma merging to mbind(), but it should have also changed the convention
> of passing start vma from queue_pages_range() (formerly check_range())
> to new_vma_page(): vma merging may have already freed that structure,
> resulting in BUG at mm/mempolicy.c:1738 and probably worse crashes.

Good catch. Cannot find fault with what I see.

Acked-by: Christoph Lameter <cl@linux.com>