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Date: Thu, 14 Apr 2016 22:01:02 +0200
From: Pavel Machek <pavel@denx.de>
To: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Ingo Molnar <mingo@kernel.org>, James Morse <james.morse@arm.com>,
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        kernel-hardening@lists.openwall.com
Subject: Re: [PATCH v2] kaslr: allow kASLR to be default over Hibernation
Message-ID: <20160414200102.GB3856@amd>
References: <20160412221659.GA18102@www.outflux.net>
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Hi!

> Since kASLR and Hibernation can not currently coexist at runtime
> on x86, the default behavior was to disable kASLR by default when
> CONFIG_HIBERNATION was present (to retain original behavior).
> 
> The behavior of kASLR on arm64 (and soon MIPS) is to be enabled by
> default when selected at build time. Since arm64 Hibernation does not
> conflict with kASLR, this fixes the hibernation argument parsing to be
> x86-specific. Additionally, since end users want to be able to select
> kASLR on x86 by default at build time, create CONFIG_RANDOMIZE_BASE_ON
> that is present only on x86.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>

I believe this is bad idea. arm64 shows that kaslr and hibernation can
coexist, and hibernation is still useful when your battery runs out.

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html