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From: Paul Mackerras <paulus@samba.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Stanimir Varbanov <svarbanov@mm-sol.com>,
	Theodore Ts'o <tytso@mit.edu>,
	Rob Herring <rob.herring@calxeda.com>,
	Pawel Moll <pawel.moll@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Stephen Warren <swarren@wwwdotorg.org>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Matt Mackall <mpm@selenic.com>,
	Herbert Xu <herbert@gondor.hengli.com.au>,
	linux-kernel@vger.kernel.org, Rob Landley <rob@landley.net>,
	devicetree@vger.kernel.org, linux-doc@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-arm-msm@vger.kernel.org
Subject: Re: [PATCH 0/2] Add support for Qualcomm's PRNG
Date: Thu, 10 Oct 2013 21:41:40 +1100	[thread overview]
Message-ID: <20131010104140.GE9906@iris.ozlabs.ibm.com> (raw)
In-Reply-To: <52557137.5050200@zytor.com>

On Wed, Oct 09, 2013 at 08:07:35AM -0700, H. Peter Anvin wrote:

> consider the PowerPC random number generator[1]) and

[snip]

> [1] which has a known first-order bias which they "correct" for by
> XORing two datums together in a very simple data reduction step.

65 actually, not two.

> However, if their random source has bias it is extremely likely it also
> has nonzero correlations, which require stronger reductions.  It would

The correlations are essentially zero, by design, and experiment
confirms it.  Did you see my mail on the kvm list where I explained
how it works?

Paul.

  parent reply	other threads:[~2013-10-10 10:41 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-03 14:52 [PATCH 0/2] Add support for Qualcomm's PRNG Stanimir Varbanov
2013-10-03 14:52 ` [PATCH 1/2] ARM: DT: msm: Add Qualcomm's PRNG driver binding document Stanimir Varbanov
2013-10-03 14:52 ` [PATCH 2/2] hwrng: msm: Add PRNG support for MSM SoC's Stanimir Varbanov
2013-10-03 19:25   ` Stephen Boyd
2013-10-04 16:31     ` Stanimir Varbanov
2013-10-04 16:37       ` Stephen Boyd
2013-10-09  8:23         ` Stanimir Varbanov
     [not found] ` <1380811955-18085-1-git-send-email-svarbanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
2013-10-03 16:51   ` [PATCH 0/2] Add support for Qualcomm's PRNG Theodore Ts'o
     [not found]     ` <20131003165130.GA11974-AKGzg7BKzIDYtjvyW6yDsg@public.gmane.org>
2013-10-04 16:23       ` Stanimir Varbanov
     [not found]         ` <524EEB96.6040707-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
2013-10-04 18:10           ` Theodore Ts'o
2013-10-09 14:46             ` Stanimir Varbanov
2013-10-09 15:07               ` H. Peter Anvin
2013-10-09 16:03                 ` Theodore Ts'o
2013-10-09 16:24                   ` H. Peter Anvin
2013-10-10 10:41                 ` Paul Mackerras [this message]
2013-10-10 15:08                   ` H. Peter Anvin
2013-10-10 13:47                 ` Stanimir Varbanov
2013-10-11  7:05                   ` Clemens Ladisch

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