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Date:   Mon, 26 Aug 2019 14:13:40 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Henry Burns <henrywolfeburns@gmail.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Henry Burns <henryburns@google.com>,
        Minchan Kim <minchan@kernel.org>,
        Nitin Gupta <ngupta@vflare.org>,
        Shakeel Butt <shakeelb@google.com>,
        Jonathan Adams <jwadams@google.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2 v2] mm/zsmalloc.c: Fix race condition in
 zs_destroy_pool
Message-ID: <20190826051340.GA26785@jagdpanzerIV>
References: <20190809181751.219326-1-henryburns@google.com>
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 <20190822162302.6fdda379ada876e46a14a51e@linux-foundation.org>
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On (08/23/19 04:10), Henry Burns wrote:
> > Thanks.  So we have a couple of races which result in memory leaks?  Do
> > we feel this is serious enough to justify a -stable backport of the
> > fixes?
> 
> In this case a memory leak could lead to an eventual crash if
> compaction hits the leaked page. I don't know what a -stable
> backport entails, but this crash would only occur if people are
> changing their zswap backend at runtime
> (which eventually starts destruction).

Well, zram/zsmalloc is not only for swapping, but it's also a virtual
block device which can be created or destroyed dynamically. So it looks
like a potential -stable material.

Minchan?

	-ss