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Date: Fri, 1 Dec 2017 14:31:45 +0100
From: Michal Hocko <mhocko@kernel.org>
To: Roman Gushchin <guro@fb.com>
Cc: linux-mm@vger.kernel.org, Vladimir Davydov <vdavydov.dev@gmail.com>,
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Subject: Re: [PATCH v13 5/7] mm, oom: add cgroup v2 mount option for
 cgroup-aware OOM killer
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On Fri 01-12-17 13:15:38, Roman Gushchin wrote:
[...]
> So, maybe we just need to return -EAGAIN (or may be -ENOTSUP) on any read/write
> attempt if option is not enabled?

Yes, that would work as well. ENOTSUP sounds better to me.
-- 
Michal Hocko
SUSE Labs