From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754355Ab1GKUPX (ORCPT ); Mon, 11 Jul 2011 16:15:23 -0400 Received: from e6.ny.us.ibm.com ([32.97.182.146]:35321 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753794Ab1GKUPW (ORCPT ); Mon, 11 Jul 2011 16:15:22 -0400 Date: Mon, 11 Jul 2011 13:15:08 -0700 From: "Paul E. McKenney" To: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xensource.com, julie Sullivan , linux-kernel@vger.kernel.org Subject: Re: PROBLEM: 3.0-rc kernels unbootable since -rc3 Message-ID: <20110711201508.GN2245@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20110710171626.GK6014@linux.vnet.ibm.com> <20110710173530.GA16954@linux.vnet.ibm.com> <20110710214639.GP6014@linux.vnet.ibm.com> <20110710231449.GQ6014@linux.vnet.ibm.com> <20110711162450.GA22913@dumpdata.com> <20110711171337.GK2245@linux.vnet.ibm.com> <20110711193021.GA2996@dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110711193021.GA2996@dumpdata.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 11, 2011 at 03:30:22PM -0400, Konrad Rzeszutek Wilk wrote: > > > > Hmmm... Does the stall repeat about every 3.5 minutes after the first stall? > > Starting Configure read-only root support... > [ 81.335070] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=60002 jiffies) > [ 81.335091] sending NMI to all CPUs: > [ 261.367071] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=240034 jiffies) > [ 261.367092] sending NMI to all CPUs: > [ 441.399066] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=420066 jiffies) > [ 441.399089] sending NMI to all CPUs: OK, then the likely cause is something hanging onto the CPU. Do the later stalls also show stack traces? If so, what shows up? (Documentation/RCU/stallwarn.txt for more info on this.) > > > > One thing to try would be to disable CONFIG_RCU_FAST_NO_HZ. I wouldn't > > expect this to have any effect, but might be worth a try. It is really > > Did not help. Well, I guess it met my expectations. Thank you for trying it! Thanx, Paul > > intended for small battery-powered systems. > >