From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Mackall Subject: Re: IRQF_SAMPLE_RANDOM question... Date: Mon, 06 Apr 2009 12:01:23 -0700 Message-ID: <1239044483.14392.55.camel@calx> References: <200904061430.26276.rgetz@blackfin.uclinux.org> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Peterson To: Robin Getz Return-path: Received: from waste.org ([66.93.16.53]:39126 "EHLO waste.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759366AbZDFVN0 (ORCPT ); Mon, 6 Apr 2009 17:13:26 -0400 In-Reply-To: <200904061430.26276.rgetz@blackfin.uclinux.org> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 2009-04-06 at 14:30 -0400, Robin Getz wrote: > Although there was some discussion > http://thread.gmane.org/gmane.linux.kernel/680723 > > about removing IRQF_SAMPLE_RANDOM from the remaining network drivers in May of > 2008, but they still appears to be there in 2.6.29. > > drivers/net/ibmlana.c > drivers/net/macb.c > drivers/net/3c523.c > drivers/net/3c527.c > drivers/net/netxen/netxen_nic_main.c > drivers/net/cris/eth_v10.c > drivers/net/xen-netfront.c > drivers/net/atlx/atl1.c > drivers/net/qla3xxx.c > drivers/net/tg3.c > drivers/net/niu.c > > So what is the plan? If I send a patch to add IRQF_SAMPLE_RANDOM to others > (like the Blackfin) networking drivers - will it get rejected? > > We have lots of embedded headless systems (no keyboard/mouse, no soundcard, no > video) systems with *no* sources of entropy - and people using SSL. I'd rather add a random_sample_network call somewhere reasonably central in the network stack. Then we can use the knowledge that the sample is network-connected in the random core to decide how to measure its entropy. The trouble with IRQF_SAMPLE_RANDOM is that many of its users are technically bogus as entropy sources in the current model. I'm eventually going to move the RNG away from the strict theoretical entropy accounting model to a more pragmatic one which will be much happier with iffy entropy sources, but that's a ways off. -- http://selenic.com : development and support for Mercurial and Linux