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Date:   Thu, 26 Sep 2019 15:48:34 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Vitaly Wool <vitalywool@gmail.com>
Cc:     Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        Markus Linnala <markus.linnala@gmail.com>, stable@kernel.org,
        Dan Streetman <ddstreet@ieee.org>,
        Vlastimil Babka <vbabka@suse.cz>
Subject: Re: [PATCH] z3fold: claim page in the beginning of free
Message-Id: <20190926154834.132f40363f5805a7a5cb347a@linux-foundation.org>
In-Reply-To: <20190926104844.4f0c6efa1366b8f5741eaba9@gmail.com>
References: <20190926104844.4f0c6efa1366b8f5741eaba9@gmail.com>
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On Thu, 26 Sep 2019 10:48:44 +0200 Vitaly Wool <vitalywool@gmail.com> wrote:

> There's a really hard to reproduce race in z3fold between
> z3fold_free() and z3fold_reclaim_page(). z3fold_reclaim_page()
> can claim the page after z3fold_free() has checked if the page
> was claimed and z3fold_free() will then schedule this page for
> compaction which may in turn lead to random page faults (since
> that page would have been reclaimed by then). Fix that by
> claiming page in the beginning of z3fold_free().
> 

I take it from the email headers that a

Cc: <stable@vger.kernel.org>

was intended?