linux-kernel - Re: [PATCH v10 3/3] mm: add anonymous vma name refcounting

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Message-ID: <YWP3c/bozz5npQ8O@dhcp22.suse.cz>
Date:   Mon, 11 Oct 2021 10:36:03 +0200
From:   Michal Hocko <mhocko@...e.com>
To:     Kees Cook <keescook@...omium.org>
Cc:     Suren Baghdasaryan <surenb@...gle.com>,
        Pavel Machek <pavel@....cz>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
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Subject: Re: [PATCH v10 3/3] mm: add anonymous vma name refcounting

On Fri 08-10-21 13:58:01, Kees Cook wrote:
> - Strings for "anon" specifically have no required format (this is good)
>   it's informational like the task_struct::comm and can (roughly)
>   anything. There's no naming convention for memfds, AF_UNIX, etc. Why
>   is one needed here? That seems like a completely unreasonable
>   requirement.

I might be misreading the justification for the feature. Patch 2 is
talking about tools that need to understand memeory usage to make
further actions. Also Suren was suggesting "numbering convetion" as an
argument against. 

So can we get a clear example how is this being used actually? If this
is just to be used to debug by humans than I can see an argument for
human readable form. If this is, however, meant to be used by tools to
make some actions then the argument for strings is much weaker.
-- 
Michal Hocko
SUSE Labs