From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758100Ab3KMG3G (ORCPT ); Wed, 13 Nov 2013 01:29:06 -0500 Received: from dmz-mailsec-scanner-8.mit.edu ([18.7.68.37]:62846 "EHLO dmz-mailsec-scanner-8.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751047Ab3KMG3C (ORCPT ); Wed, 13 Nov 2013 01:29:02 -0500 X-AuditID: 12074425-b7fd96d000000c39-42-52831c2dfad1 Date: Wed, 13 Nov 2013 01:28:57 -0500 From: Greg Price To: "Theodore Ts'o" , "H. Peter Anvin" , linux-kernel@vger.kernel.org, Jiri Kosina Subject: Re: [PATCH 00/11] random: code cleanups Message-ID: <20131113062857.GB8043@ringworld.MIT.EDU> References: <52830546.8010002@zytor.com> <20131113042303.GY8043@ringworld.MIT.EDU> <20131113060807.GA11394@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131113060807.GA11394@thunk.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrMIsWRmVeSWpSXmKPExsUixG6noqsr0xxksGabhMW0jeIWu+csZrG4 vGsOmwOzx5kFR9g9Pm+S8zjR8oU1gDmKyyYlNSezLLVI3y6BK2PtnX7Wgn6Oij2XnBsYN7N1 MXJySAiYSMycvokdwhaTuHBvPVCci0NIYDaTxO6zV1khnI2MEo/+T2GGcH4xSnzbcB+snUVA VWLx3w9g7WwCChI/5q8DKxIR6GaUWHf3LVhCWMBAYtfOLhYQm1fAVGLxuy9gzUIClRITvz+C igtKnJz5BMxmFtCSuPHvJVMXIweQLS2x/B8HSJhTQF9i8a8jYCWiAioSU05uY5vAKDALSfcs JN2zELoXMDKvYpRNya3SzU3MzClOTdYtTk7My0st0rXQy80s0UtNKd3ECA5bF9UdjBMOKR1i FOBgVOLhtYhpChJiTSwrrsw9xCjJwaQkyntGpDlIiC8pP6UyI7E4I76oNCe1+BCjBAezkgjv AWGgHG9KYmVValE+TEqag0VJnPcWh32QkEB6YklqdmpqQWoRTFaGg0NJgjdNGqhRsCg1PbUi LTOnBCHNxMEJMpwHaDgfSA1vcUFibnFmOkT+FKOilDjvVSmghABIIqM0D64XllZeMYoDvSLM 2wHSzgNMSXDdr4AGMwENtihuAhlckoiQkmpgXHz3RlHiruObW2MXWAZHxT67l6g2w++hwy3m 3a5nmHYbbPt8MVFS/kpY4bRmjgkvFLMPvGDPPX7n64eD766urjjgayf473txbGVElfb8m69f XV/wxmeGwPrpMg2HM9fuPHN5qsp6dbukzYeFr7Nnnvjy89wq65/2LgyHi7Z1f/9lb5acnG51 qVSJpTgj0VCLuag4EQAMRHekBgMAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 13, 2013 at 01:08:07AM -0500, Theodore Ts'o wrote: > On Tue, Nov 12, 2013 at 11:23:03PM -0500, Greg Price wrote: > > That's a good idea. I've worried about the same thing, but hadn't > > thought of that solution. > > I think the key is that we set a default of requiring 128 bits, or 5 > minutes, with boot-line options to change the defaults. BTW, with the > changes that are scheduled for 3.13, this shouldn't be a problem on > most desktops. From my T430s laptop: [...] > > So even without adding device attach times (which is on the todo list) > the /dev/urandom pool is getting an estimated 128 bits of entropy > almost two seconds *before* the root file system is remouted > read/write. Great! > This is why I've been working improving the random driver's efficiency > in getting the urandom pool as soon as possible, as higher priority > than adding blocking-on-boot for /dev/urandom. Makes sense. Blocking on boot is only sustainable anyway if it rarely lasts past early boot. Greg