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Date: Wed, 2 May 2018 14:56:45 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: "Tobin C. Harding" <me@tobin.cc>
Cc: linux-kernel@vger.kernel.org, Linus Torvalds
 <torvalds@linux-foundation.org>, Randy Dunlap <rdunlap@infradead.org>,
 Steven Rostedt <rostedt@goodmis.org>, Kees Cook <keescook@chromium.org>,
 Anna-Maria Gleixner <anna-maria@linutronix.de>, "Theodore Ts'o"
 <tytso@mit.edu>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Arnd
 Bergmann <arnd@arndb.de>
Subject: Re: [PATCH 3/3] vsprintf: Add use-early-random-bytes cmd line
 option
Message-Id: <20180502145645.a1fa72b86f2501432f003edc@linux-foundation.org>
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On Wed,  2 May 2018 09:33:40 +1000 "Tobin C. Harding" <me@tobin.cc> wrote:

> Currently if an attempt is made to print a pointer before there is
> enough entropy then '(____ptrval____)' is printed.  This makes debugging
> early stage stack traces difficult.  We can relax the requirement for
> cryptographically secure hashing when debugging while still maintaining
> pointer hashing behaviour.
> 
> Add a command line option 'use-early-random-bytes'.  When enabled get
> key material from the hw RNG if available.

Documentation/admin-guide/kernel-parameters.rst, please.

> This option should NOT be enabled on production kernels.

And the documentation should explain why this recommendation is made. 
Here was I scratching my head wondering why this feature isn't just
permanently enabled.  Still scratching away...