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From: "Jörn Engel" <joern@logfs.org>
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: John Stultz <john.stultz@linaro.org>,
	Stephan Mueller <smueller@chronox.de>,
	LKML <linux-kernel@vger.kernel.org>,
	dave.taht@bufferbloat.net,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] /dev/random: Insufficient of entropy on many architectures
Date: Thu, 12 Sep 2013 20:00:11 -0400	[thread overview]
Message-ID: <20130913000011.GJ3809@logfs.org> (raw)
In-Reply-To: <20130912233535.GI3809@logfs.org>

On Thu, 12 September 2013 19:35:36 -0400, Jörn Engel wrote:
> 
> I think the existing code is doing just fine for low interrupt loads.
> It makes sense to spend a bit more work to squeeze the last bit of
> randomness out.  But when you get lots of interrupts, you can be
> sloppy and just xor things into the pool.

Btw, if we make collection cheap enough, we can start collecting
entropy from the scheduler.  Computers are fairly deterministic, but
not that much.  The exact time when calling schedule(), the kernel
stack pointer and the userspace stack pointer all contain a bit of
entropy.  Particularly on machines that lack input and disk
randomness I would expect some benefits from this.

Jörn

--
Audacity augments courage; hesitation, fear.
-- Publilius Syrus

  reply	other threads:[~2013-09-13  1:34 UTC|newest]

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-10 11:31 [PATCH] /dev/random: Insufficient of entropy on many architectures Stephan Mueller
2013-09-10 11:46 ` Geert Uytterhoeven
2013-09-10 15:04 ` Theodore Ts'o
2013-09-10 16:54   ` Stephan Mueller
2013-09-10 18:25     ` Theodore Ts'o
2013-09-10 19:15       ` Stephan Mueller
2013-10-10  6:50       ` Pavel Machek
2013-10-14 21:13         ` Theodore Ts'o
2013-09-10 20:48   ` Geert Uytterhoeven
2013-09-10 21:14     ` Theodore Ts'o
2013-09-11  6:49       ` Stephan Mueller
2013-09-12 11:59         ` Geert Uytterhoeven
2013-09-12 12:08           ` Stephan Mueller
2013-09-12 12:15             ` Geert Uytterhoeven
2013-09-12 12:35               ` Stephan Mueller
2013-09-12 12:47                 ` Geert Uytterhoeven
2013-09-12 12:57                   ` Stephan Mueller
2013-09-12 21:18               ` Jörn Engel
2013-09-13 11:33             ` Thorsten Glaser
2013-09-12 14:25           ` Theodore Ts'o
2013-09-10 19:38 ` John Stultz
2013-09-10 19:44   ` John Stultz
2013-09-10 19:47   ` Stephan Mueller
2013-09-10 20:35     ` John Stultz
2013-09-10 20:38   ` Theodore Ts'o
2013-09-10 20:46     ` John Stultz
2013-09-10 21:10       ` Theodore Ts'o
2013-09-10 22:08         ` John Stultz
2013-09-10 22:33           ` Theodore Ts'o
2013-09-11  0:31             ` John Stultz
2013-09-11  0:50               ` Theodore Ts'o
2013-09-11  1:14                 ` John Stultz
2013-09-12 20:46                 ` H. Peter Anvin
2013-09-12 21:07                 ` Jörn Engel
2013-09-12 23:31                   ` Theodore Ts'o
2013-09-12 23:35                     ` Jörn Engel
2013-09-13  0:00                       ` Jörn Engel [this message]
2013-09-16 15:40                     ` [PATCH,RFC] random: make fast_mix() honor its name Jörn Engel
2013-09-21 21:25                       ` Theodore Ts'o
2013-09-21 21:41                         ` Theodore Ts'o
2013-09-22  3:05                           ` Theodore Ts'o
2013-09-22 21:01                             ` Jörg-Volker Peetz
2013-09-22 21:27                               ` Theodore Ts'o
2013-09-22 20:53                                 ` Jörn Engel
2013-09-22 23:36                                   ` Theodore Ts'o
2013-09-23  0:16                                     ` Jörn Engel
2013-09-23  2:43                                       ` Theodore Ts'o
2013-09-23 15:02                                         ` Jörn Engel
2013-09-23  7:39                                 ` Jörg-Volker Peetz
2013-09-22 20:31                           ` Jörn Engel
2013-09-22 20:14                         ` Jörn Engel
2013-09-12 21:31           ` [PATCH] /dev/random: Insufficient of entropy on many architectures Jörn Engel
2013-09-13  5:36             ` Stephan Mueller
2013-09-13 11:54               ` Thorsten Glaser
2013-09-13 19:29                 ` Theodore Ts'o
2013-09-13 15:26               ` Jörn Engel
2013-09-13 18:59               ` Theodore Ts'o
2013-09-15 11:12                 ` Stephan Mueller

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