From mboxrd@z Thu Jan 1 00:00:00 1970 From: Danny Milosavljevic Subject: Re: /dev/urandom Date: Tue, 10 Jul 2018 20:58:43 +0200 Message-ID: <20180710205843.68793bed@scratchpost.org> References: <20180710182211.75442f8b@scratchpost.org> <20180710182809.GA13244@jasmine.lan> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; boundary="Sig_/k8+pw1aNW5=A_4BB9uFev9A"; protocol="application/pgp-signature" Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:36343) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fcxqd-0005Gx-KI for guix-devel@gnu.org; Tue, 10 Jul 2018 14:58:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fcxqZ-0005hA-O8 for guix-devel@gnu.org; Tue, 10 Jul 2018 14:58:51 -0400 Received: from dd26836.kasserver.com ([85.13.145.193]:41926) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fcxqZ-0005fY-G7 for guix-devel@gnu.org; Tue, 10 Jul 2018 14:58:47 -0400 In-Reply-To: <20180710182809.GA13244@jasmine.lan> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Leo Famulari Cc: guix-devel@gnu.org --Sig_/k8+pw1aNW5=A_4BB9uFev9A Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Leo, On Tue, 10 Jul 2018 14:28:09 -0400 Leo Famulari wrote: > On Tue, Jul 10, 2018 at 06:22:11PM +0200, Danny Milosavljevic wrote: > > Hi, > >=20 > > u-boot tools/sunxi-spl-image-builder.c reads from /dev/urandom . > >=20 > > For reproducibility I'd like this to be a static file. Do we already h= ave one > > for this purpose? =20 >=20 > You could use /dev/zero. What does the program do with the random data? It writes an image file. Since that image is later written to flash storage (by the user), the program randomizes the data in order to increase longevi= ty. Then it stores the random data used as well. See http://soc.yonsei.ac.kr/Abstract/International_journal/pdf/106_Data%20R= andomization%20Scheme%20for%20Endurance%20Enhancement%20and%20Interference%= 20Mitigation%20of%20Multilevel%20Flash%20Memory%20Devices.pdf --Sig_/k8+pw1aNW5=A_4BB9uFev9A Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEds7GsXJ0tGXALbPZ5xo1VCwwuqUFAltFAeMACgkQ5xo1VCww uqWQbgf/aVRcJzS0F3kMwaAJovB5nqaN1UnKT1wsdLmYpiGCPF85eKnt2aRDv0p3 y8BqiQGOp2JK2TJdVzAPIhE1/n8rKgSVCGpDiLmspfPhrAqPllyVGxLHTq7zM6IN Sn6uZ3bux+C1XG4It257mUmhLMo370bZoLN/CiPJt4RPe0yQ57Ey/UVhrmoFHqAF +YTIyii0lRwicc2QyF2PeRDzTI0C3UTfC/yqZFusPjxv6YXj7+xzHAgZaa0EfUaB vUZIpg+SoP8eZmUwpzt9MqyY7erFM84dJ2ZBwkVdsR9ku+03DFThXQQJAlyX2E+H OXUSAWaHKEFsZX478j3C2blWT2P+Cg== =HqhG -----END PGP SIGNATURE----- --Sig_/k8+pw1aNW5=A_4BB9uFev9A--