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Date:   Mon, 22 Feb 2021 07:34:52 +0000
From:   Matthew Garrett <mjg59@srcf.ucam.org>
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
Message-ID: <20210222073452.GA30403@codon.org.uk>
References: <20210208084920.2884-1-rppt@kernel.org>
 <20210208084920.2884-9-rppt@kernel.org>
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On Mon, Feb 08, 2021 at 10:49:18AM +0200, Mike Rapoport wrote:

> 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.

Sorry for being a bit late to this - from the point of view of running
processes (and even the kernel once resume is complete), hibernation is
effectively equivalent to suspend to RAM. Why do they need to be handled
differently here?