From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 30 Sep 2001 01:43:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 30 Sep 2001 01:43:19 -0400 Received: from e23.nc.us.ibm.com ([32.97.136.229]:37595 "EHLO e23.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Sun, 30 Sep 2001 01:43:08 -0400 Date: Sat, 29 Sep 2001 22:49:57 -0700 From: "Martin J. Bligh" Reply-To: "Martin J. Bligh" To: Alan Cox , Andrew Morton cc: linux-kernel Subject: Re: Adding a printk in start_secondary breaks 2.4.10, not 2.4.9 ?? Message-ID: <1076417648.1001803797@[10.10.1.2]> In-Reply-To: X-Mailer: Mulberry/2.0.5 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >> FWIW, I still think that means that the console locking changes are >> broken - adding a printk shouldn't panic the kernel. I'll go look at >> the console locking changes (*and* fix my disgusting hack ;-) ) > > I suspect the panic has nothing to do with adding the printk, but merely > that the timing patterns of your disgusting hack have changed > > Happy logical analysers 8) OK, you're right ;-) It turned out to be a race between init_idle and reschedule_idle, that is a generic bug, but is revealed by the timing changes that my printk introduces (both in standard SMP and NUMA kernels, if you turn on serial consoles). See imminent post for a patch. Having fixed the real problem, I can now axe that disgusting hack ;-) Thanks for your help, Martin.