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Date: Fri, 10 Sep 2010 16:44:13 +0200
From: Andrea Arcangeli <aarcange@redhat.com>
To: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Hugh Dickins <hughd@google.com>,
        Christoph Lameter <cl@linux.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Rik van Riel <riel@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
        Andi Kleen <andi@firstfloor.org>, linux-mm <linux-mm@kvack.org>
Subject: Re: [PATCH 4/4] hugetlb, rmap: add BUG_ON(!PageLocked) in
 hugetlb_add_anon_rmap()
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On Fri, Sep 10, 2010 at 01:23:06PM +0900, Naoya Horiguchi wrote:
> Confirming page lock is held in hugetlb_add_anon_rmap() may be useful
> to detect possible future problems.
> 
> Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> ---
>  mm/rmap.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)

Acked-by: Andrea Arcangeli <aarcange@redhat.com>

It should probably be a VM_BUG_ON like do_page_add_anon_rmap, but
given the tiny hugetlbfs userbase it's ok.