From: Stephan =?ISO-8859-1?Q?M=FCller?= <smueller@chronox.de>
Subject: Re: [RFC PATCH v12 3/4] Linux Random Number Generator
Date: Wed, 19 Jul 2017 08:25:55 +0200
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Cc: Sandy Harris <sandyinchina@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Jason A. Donenfeld" <jason@zx2c4.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
To: Theodore Ts'o <tytso@mit.edu>
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Am Mittwoch, 19. Juli 2017, 03:51:33 CEST schrieb Theodore Ts'o:

Hi Theodore,

> If the real unpredictability is really coming from the interrupts
> changing the state of the CPU microarchitecture, the real question is
> how many interrupts do you need before you consider things
> "unpredictable" to an adequate level of security?  Arguing that we
> should turn down the "interrupts per bit of entropy" in
> drivers/char/random.c is a much more honest way of having that
> discussion.

Please answer on the concerns given in [1] which explains that we cannot allow 
turning that knob in the current implementation.

[1] https://www.spinics.net/lists/linux-crypto/msg26316.html

Ciao
Stephan