From: Kent Borg Subject: Re: [PATCH 4/5] tsc: wire up entropy generation function Date: Tue, 14 Jun 2011 16:04:05 -0400 Message-ID: <4DF7BEB5.1070006@borg.org> References: <1308002818-27802-1-git-send-email-jarod@redhat.com> <1308002818-27802-5-git-send-email-jarod@redhat.com> <4DF690E4.1060004@zytor.com> <4DF6ADD0.6080607@borg.org> <4DF6BDB4.2060201@zytor.com> <4DF75688.2050509@borg.org> <1308062037.15617.71.camel@calx> <4DF79EF1.3010004@borg.org> <1308074432.15617.136.camel@calx> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: "H. Peter Anvin" , Venkatesh Pallipadi , Jarod Wilson , linux-crypto@vger.kernel.org, Thomas Gleixner , Ingo Molnar , John Stultz , Herbert Xu , "David S. Miller" , Suresh Siddha To: Matt Mackall Return-path: Received: from borg.org ([64.105.205.123]:59778 "EHLO borg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750947Ab1FNUEI (ORCPT ); Tue, 14 Jun 2011 16:04:08 -0400 In-Reply-To: <1308074432.15617.136.camel@calx> Sender: linux-crypto-owner@vger.kernel.org List-ID: Matt Mackall wrote: > [network adapters are] a great source of potential entropy, a bad > source of guaranteed entropy. The current RNG tries to do > accounting on the latter. Accounting on the former is extremely > suspect. So we need a patch that: - Deletes the IRQF_SAMPLE_RANDOM mention in feature-removal-schedule.txt, - Restores instances of IRQF_SAMPLE_RANDOM in drivers, and - Changes the credit_entropy_bits() to credit less entropy*. * The code seems to only handle integer values of entropy. Maybe when crediting, choose between 1 and 0 credits. Then once that kernel makes it into the field, a bunch of entropy starved machines will no longer be entropy starved. A few machines that are run by people who worship an entropy estimate will still have to install mice and users, explicit RNGs, etc., but entropy will flow. Make sense? -kb