From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755278AbYIWTkT (ORCPT ); Tue, 23 Sep 2008 15:40:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752097AbYIWTkE (ORCPT ); Tue, 23 Sep 2008 15:40:04 -0400 Received: from main.gmane.org ([80.91.229.2]:44531 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751648AbYIWTkB (ORCPT ); Tue, 23 Sep 2008 15:40:01 -0400 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Sitsofe Wheeler Subject: Re: How how latent should non-preemptive scheduling be? Date: Tue, 23 Sep 2008 20:39:56 +0100 Message-ID: <48D9460C.5040504@yahoo.com> References: <48D39312.9000400@yahoo.com> <20080922115749.GE14301@elte.hu> <48D88DB4.9020003@yahoo.com> <20080923115323.GA27240@elte.hu> <48D919A9.5000708@yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@ger.gmane.org Cc: Ingo Molnar , Peter Zijlstra , Arjan van de Ven , linux-kernel@vger.kernel.org, Steven Rostedt X-Gmane-NNTP-Posting-Host: 87.112.14.28.plusnet.ptn-ag1.dyn.plus.net User-Agent: Thunderbird 2.0.0.16 (Macintosh/20080707) In-Reply-To: <48D919A9.5000708@yahoo.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sitsofe Wheeler wrote: > I've been struggling to boot -tip/master - currently it blows up just > after printing SLUB information saying: > > BUG: unable to handle kernel NULL pointer dereference at 00000004 > IP: [] account_system_time+0x48/0x120 > *pde = 00000000 > Thread overran stack, or stack corrupted > Oops: 0002 [#1] PREEMPT OK this BUG seems to have gone away in the past few hours. Ingo when you were asking for the ftrace report I presume that would be for a non preempt kernel (as a preemptive one only showed a very worst latency of 19657 us in one exceptional case)? -- Sitsofe | http://sucs.org/~sits/