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Date: Thu, 29 Mar 2012 22:26:28 +0200
From: Andrea Arcangeli <aarcange@redhat.com>
To: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Sasha Levin <levinsasha928@gmail.com>, Hugh Dickins <hughd@google.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        stable@vger.kernel.org
Subject: Re: [PATCH] pagemap: remove remaining unneeded spin_lock()
Message-ID: <20120329202628.GD20930@redhat.com>
References: <1333010379-31126-1-git-send-email-n-horiguchi@ah.jp.nec.com>
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On Thu, Mar 29, 2012 at 04:39:39AM -0400, Naoya Horiguchi wrote:
> commit: 025c5b2451e4 "thp: optimize away unnecessary page table locking"
> moves spin_lock() into pmd_trans_huge_lock() in order to avoid locking
> unless pmd is for thp. So this spin_lock() is a bug.
> 
> Reported-by: Sasha Levin <levinsasha928@gmail.com>
> Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> Cc: stable@vger.kernel.org

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