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Date:   Mon, 24 Aug 2020 17:10:45 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Qian Cai <cai@lca.pw>
Cc:     Alex Shi <alex.shi@linux.alibaba.com>, akpm@linux-foundation.org,
        Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        cgroups@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, sfr@canb.auug.org.au,
        linux-next@vger.kernel.org
Subject: Re: [Resend PATCH 1/6] mm/memcg: warning on !memcg after readahead
 page charged
Message-ID: <20200824151045.GC3415@dhcp22.suse.cz>
References: <1597144232-11370-1-git-send-email-alex.shi@linux.alibaba.com>
 <20200820145850.GA4622@lca.pw>
 <20200824145201.GB4337@lca.pw>
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On Mon 24-08-20 10:52:02, Qian Cai wrote:
> On Thu, Aug 20, 2020 at 10:58:50AM -0400, Qian Cai wrote:
> > On Tue, Aug 11, 2020 at 07:10:27PM +0800, Alex Shi wrote:
> > > Since readahead page is charged on memcg too, in theory we don't have to
> > > check this exception now. Before safely remove them all, add a warning
> > > for the unexpected !memcg.
> > > 
> > > Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
> > > Acked-by: Michal Hocko <mhocko@suse.com>
> > 
> > This will trigger,
> 
> Andrew, Stephen, can you drop this series for now? I did manage to trigger this
> warning on all arches, powerpc, x86 and arm64 (below).

Yes, I do agree. See http://lkml.kernel.org/r/20200824151013.GB3415@dhcp22.suse.cz
-- 
Michal Hocko
SUSE Labs