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Date:   Mon, 29 Apr 2019 12:17:32 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Jiri Slaby <jslaby@suse.cz>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        cgroups@vger.kernel.org, mm <linux-mm@kvack.org>,
        Linux kernel mailing list <linux-kernel@vger.kernel.org>
Subject: Re: memcg causes crashes in list_lru_add
Message-ID: <20190429101732.GB21837@dhcp22.suse.cz>
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 <2cbfb8dc-31f0-7b95-8a93-954edb859cd8@suse.cz>
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On Mon 29-04-19 11:25:48, Jiri Slaby wrote:
> On 29. 04. 19, 10:16, Jiri Slaby wrote:
[...]
> > Any idea how to fix this mess?
> 
> memcg_update_all_list_lrus should take care about resizing the array. So
> it looks like list_lru_from_memcg_idx returns a stale pointer to
> list_lru_from_kmem and then to list_lru_add. Still investigating.

I am traveling and on a conference this week. Please open a bug and if
this affects upstream kernel then report upstream as well. Cc linux-mm
and memcg maintainers. This doesn't ring bells immediately. I do not
remember any large changes recently.
-- 
Michal Hocko
SUSE Labs