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Date: Tue, 8 Dec 2009 14:35:06 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: n-horiguchi@ah.jp.nec.com
Cc: LKML <linux-kernel@vger.kernel.org>, hugh.dickins@tiscali.co.uk,
       linux-mm <linux-mm@kvack.org>, stable@kernel.org
Subject: Re: [PATCH] mm hugetlb x86: fix hugepage memory leak in mincore()
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On Mon, 07 Dec 2009 16:59:14 +0900
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> wrote:

> Most callers of pmd_none_or_clear_bad() check whether the target
> page is in a hugepage or not, but mincore() and walk_page_range()
> do not check it. So if we use mincore() on a hugepage on x86 machine,
> the hugepage memory is leaked as shown below.
> This patch fixes it by extending mincore() system call to support hugepages.

This bug is fairly embarrassing.  I tagged the patch for a -stable
backport.