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Date:   Wed, 23 Dec 2020 08:57:12 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Jann Horn <jannh@google.com>, Minchan Kim <minchan@kernel.org>,
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Subject: Re: [PATCH 1/2] mm/madvise: allow process_madvise operations on
 entire memory range
Message-ID: <20201223075712.GA4719@lst.de>
References: <20201124053943.1684874-1-surenb@google.com> <20201124053943.1684874-2-surenb@google.com> <20201125231322.GF1484898@google.com> <CAG48ez0UKYCdgyW91SmOcT52vbLFz9RjLpaucWpj6bTrgQCwnA@mail.gmail.com> <20201222134438.GA7170@infradead.org> <CAJuCfpGiVS69kznSrAdosxnRd-zgXPJd8MXou=gd8K8j7xLMjA@mail.gmail.com>
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On Tue, Dec 22, 2020 at 09:48:43AM -0800, Suren Baghdasaryan wrote:
> Thanks for the feedback! The use case is userspace memory reaping
> similar to oom-reaper. Detailed justification is here:
> https://lore.kernel.org/linux-mm/20201124053943.1684874-1-surenb@google.com

Given that this new variant of process_madvise

  a) does not work on an address range
  b) is destructive
  c) doesn't share much code at all with the rest of process_madvise

Why not add a proper separate syscall?