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From:   Shakeel Butt <shakeelb@google.com>
Date:   Tue, 21 Apr 2020 12:13:34 -0700
Message-ID: <CALvZod4Rc0a1LBE7DCa0U8xA3a3N1u7g=mDjRw0cJEzvK62vmA@mail.gmail.com>
Subject: Re: [PATCH 01/18] mm: fix NUMA node file count error in replace_page_cache()
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Joonsoo Kim <js1304@gmail.com>,
        Alex Shi <alex.shi@linux.alibaba.com>,
        Hugh Dickins <hughd@google.com>,
        Michal Hocko <mhocko@suse.com>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Roman Gushchin <guro@fb.com>, Linux MM <linux-mm@kvack.org>,
        Cgroups <cgroups@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Kernel Team <kernel-team@fb.com>
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On Mon, Apr 20, 2020 at 3:11 PM Johannes Weiner <hannes@cmpxchg.org> wrote:
>
> When replacing one page with another one in the cache, we have to
> decrease the file count of the old page's NUMA node and increase the
> one of the new NUMA node, otherwise the old node leaks the count and
> the new node eventually underflows its counter.
>
> Fixes: 74d609585d8b ("page cache: Add and replace pages using the XArray")
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>

Reviewed-by: Shakeel Butt <shakeelb@google.com>