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Date:   Mon, 8 Feb 2021 11:18:37 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Mike Rapoport <rppt@kernel.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Andy Lutomirski <luto@kernel.org>,
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Subject: Re: [PATCH v17 08/10] PM: hibernate: disable when there are active
 secretmem users
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References: <20210208084920.2884-1-rppt@kernel.org>
 <20210208084920.2884-9-rppt@kernel.org>
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On Mon 08-02-21 10:49:18, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
> 
> It is unsafe to allow saving of secretmem areas to the hibernation
> snapshot as they would be visible after the resume and this essentially
> will defeat the purpose of secret memory mappings.
> 
> Prevent hibernation whenever there are active secret memory users.

Does this feature need any special handling? As it is effectivelly
unevictable memory then it should behave the same as other mlock, ramfs
which should already disable hibernation as those cannot be swapped out,
no?

-- 
Michal Hocko
SUSE Labs