From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: Hardware bug or kernel bug? Date: Tue, 17 Oct 2006 09:10:05 +0200 Message-ID: <20061017071005.GA1742@ff.dom.local> References: <20061013085605.GA1690@ff.dom.local> <200610131724.40631.dj@david-web.co.uk> <20061016102500.GA1709@ff.dom.local> <200610161532.38663.dj@david-web.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linux Kernel , netdev@vger.kernel.org Return-path: Received: from poczta.o2.pl ([193.17.41.142]:60076 "EHLO poczta.o2.pl") by vger.kernel.org with ESMTP id S932177AbWJQHFG (ORCPT ); Tue, 17 Oct 2006 03:05:06 -0400 To: David Johnson Content-Disposition: inline In-Reply-To: <200610161532.38663.dj@david-web.co.uk> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, Oct 16, 2006 at 03:32:38PM +0100, David Johnson wrote: ... > I've found the culprit - CPU Frequency Scaling. > With it enabled I get the reboots, with it disabled I don't. That's the same > with every kernel version I've tried (2.6.19-rc1+rc2, 2.6.17.13 & Centos' > 2.6.9) The system was using the p4-clockmod driver and the ondemand governor. > > I'm still not sure exactly what the problem is - the reboots only happen in > the circumstances I've mentioned and are not triggered by changes in clock > speed alone - but disabling cpufreq seems to make it go away... I see you devoted a lot of work and time to this testing and for sure it will help people who read this to diagnose similar problems but I think it could be even more valuable if you'd try (after some rest!) to find if "Enable CPUfreq debugging" plus adding to kernel command line cpufreq.debug= (according to help screen) would return any error messages that could be send to bugzilla and/or cpufreq maintainer. Best regards, Jarek P.