From: "Theodore Ts'o" <tytso@mit.edu>
To: Stephan Mueller <smueller@chronox.de>
Cc: sandy harris <sandyinchina@gmail.com>,
linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org
Subject: Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random
Date: Tue, 29 Oct 2013 09:24:48 -0400 [thread overview]
Message-ID: <20131029132448.GB691@thunk.org> (raw)
In-Reply-To: <3160817.9DcncHidey@tauon>
On Tue, Oct 29, 2013 at 09:42:30AM +0100, Stephan Mueller wrote:
> Based on this suggestion, I now added the tests in Appendix F.46.8 where
> I disable the caches and the tests in Appendix F.46.9 where I disable
> the caches and interrupts.
What you've added in F.46 is a good start, but as a suggestiom,
instead of disabling one thing at a time, try disabling *everything*
and then see what you get, and then enabling one thing at a time. The
best thing is if you can get to the point where the amount of entropy
is close to zero. Then as you add things back, there's a much better
sense of where the unpredictability might be coming from, and whether
the unpredictability is coming from something which is fundamentally
arising from something which is chaotic or quantum effect, or just
because we don't have a good way of modelling the behavior of the
L1/L2 cache (for example) and that is spoofing your entropy estimator.
Regards,
- Ted
next prev parent reply other threads:[~2013-10-29 13:24 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-11 18:38 [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random Stephan Mueller
2013-10-12 1:45 ` Sandy Harris
2013-10-12 3:28 ` Theodore Ts'o
2013-10-12 19:04 ` Stephan Mueller
2013-10-12 20:12 ` Stephan Mueller
[not found] ` <CACXcFm=_jmeKe2YYbHDi-jTGX-23hDsDeu_weWQkr2F_FpE_6g@mail.gmail.com>
2013-10-14 13:38 ` Fwd: " Sandy Harris
2013-10-14 14:12 ` Stephan Mueller
2013-10-14 14:26 ` Stephan Mueller
2013-10-14 14:14 ` Sandy Harris
2013-10-14 14:40 ` Stephan Mueller
2013-10-14 15:18 ` Sandy Harris
2013-10-14 15:26 ` Stephan Mueller
2013-10-14 15:46 ` Sandy Harris
2013-10-14 21:33 ` Sandy Harris
2013-10-15 6:23 ` Stephan Mueller
2013-10-28 15:40 ` Stephan Mueller
2013-10-28 16:06 ` Henrique de Moraes Holschuh
2013-10-28 16:15 ` Stephan Mueller
2013-10-28 21:45 ` Theodore Ts'o
2013-10-29 8:42 ` Stephan Mueller
2013-10-29 13:24 ` Theodore Ts'o [this message]
2013-10-29 14:00 ` Stephan Mueller
2013-10-29 22:25 ` Stephan Mueller
2013-11-02 11:01 ` Pavel Machek
2013-11-02 11:12 ` Pavel Machek
2013-11-03 7:20 ` Stephan Mueller
2013-11-03 12:41 ` Theodore Ts'o
2013-11-05 12:20 ` Stephan Mueller
2013-11-06 11:49 ` Stephan Mueller
2013-11-06 12:43 ` Theodore Ts'o
2013-11-06 12:51 ` Stephan Mueller
2013-11-06 13:04 ` Theodore Ts'o
2013-11-06 13:24 ` Pavel Machek
2013-11-07 0:36 ` Nicholas Mc Guire
2013-11-07 5:21 ` Stephan Mueller
2013-11-09 22:04 ` Clemens Ladisch
2013-11-10 1:10 ` Stephan Mueller
2013-11-10 16:31 ` Clemens Ladisch
2013-11-10 17:21 ` Stephan Mueller
2013-11-10 20:28 ` Clemens Ladisch
2013-11-13 3:12 ` Stephan Mueller
2013-11-13 11:51 ` Clemens Ladisch
2013-11-13 15:15 ` Stephan Mueller
2013-11-13 17:14 ` Pavel Machek
2013-11-14 10:51 ` Clemens Ladisch
2013-11-14 18:01 ` Stephan Mueller
2013-11-14 18:30 ` Clemens Ladisch
2013-11-14 18:34 ` Stephan Mueller
2013-11-11 2:58 ` H. Peter Anvin
2013-11-07 1:03 ` Nicholas Mc Guire
2013-11-07 5:26 ` Stephan Mueller
2013-11-09 22:04 ` Clemens Ladisch
2013-11-10 1:16 ` Stephan Mueller
2013-11-03 23:32 ` Pavel Machek
2013-11-05 12:25 ` Stephan Mueller
2013-11-05 13:45 ` Stephan Mueller
2013-11-06 11:42 ` Stephan Mueller
2013-11-06 13:26 ` Pavel Machek
2013-11-07 3:12 ` Stephan Mueller
2013-11-13 3:37 ` [PATCH] CPU Jitter RNG: Executing time variation tests on bare metal Stephan Mueller
2013-10-30 12:59 ` [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random Sandy Harris
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