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Date:   Thu, 18 Jun 2020 14:41:29 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Chris Down <chris@chrisdown.name>
Cc:     Yafang Shao <laoar.shao@gmail.com>,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        Anders Roxell <anders.roxell@linaro.org>,
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Subject: Re: mm: mkfs.ext4 invoked oom-killer on i386 - pagecache_get_page
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On Thu 18-06-20 13:37:43, Chris Down wrote:
> Yafang Shao writes:
> > On Thu, Jun 18, 2020 at 5:09 AM Chris Down <chris@chrisdown.name> wrote:
> > > 
> > > Naresh Kamboju writes:
> > > >After this patch applied the reported issue got fixed.
> > > 
> > > Great! Thank you Naresh and Michal for helping to get to the bottom of this :-)
> > > 
> > > I'll send out a new version tomorrow with the fixes applied and both of you
> > > credited in the changelog for the detection and fix.
> > 
> > As we have already found that the usage around memory.{emin, elow} has
> > many limitations, I think memory.{emin, elow} should be used for
> > memcg-tree internally only, that means they can only be used to
> > calculate the protection of a memcg in a specified memcg-tree but
> > should not be exposed to other MM parts.
> 
> I agree that the current semantics are mentally taxing and we should
> generally avoid exposing the implementation details outside of memcg where
> possible. Do you have a suggested rework? :-)

I would really prefer to do that work on top of the fixes we (used to)
have in mmotm (with the fixup).
-- 
Michal Hocko
SUSE Labs