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Date:   Tue, 21 May 2019 08:50:00 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Oleksandr Natalenko <oleksandr@redhat.com>
Cc:     Minchan Kim <minchan@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tim Murray <timmurray@google.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Daniel Colascione <dancol@google.com>,
        Shakeel Butt <shakeelb@google.com>,
        Sonny Rao <sonnyrao@google.com>,
        Brian Geffon <bgeffon@google.com>
Subject: Re: [RFC 4/7] mm: factor out madvise's core functionality
Message-ID: <20190521065000.GH32329@dhcp22.suse.cz>
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On Tue 21-05-19 08:36:28, Oleksandr Natalenko wrote:
[...]
> Regarding restricting the hints, I'm definitely interested in having
> remote MADV_MERGEABLE/MADV_UNMERGEABLE. But, OTOH, doing it via remote
> madvise() introduces another issue with traversing remote VMAs reliably.
> IIUC, one can do this via userspace by parsing [s]maps file only, which
> is not very consistent, and once some range is parsed, and then it is
> immediately gone, a wrong hint will be sent.
> 
> Isn't this a problem we should worry about?

See http://lkml.kernel.org/r/20190520091829.GY6836@dhcp22.suse.cz

-- 
Michal Hocko
SUSE Labs