From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754494AbbAWXGR (ORCPT ); Fri, 23 Jan 2015 18:06:17 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:23099 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754263AbbAWXGM (ORCPT ); Fri, 23 Jan 2015 18:06:12 -0500 Message-ID: <54C2D3B5.5080808@oracle.com> Date: Fri, 23 Jan 2015 18:05:25 -0500 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: paulmck@linux.vnet.ibm.com CC: Lai Jiangshan , Ingo Molnar , Peter Zijlstra , LKML , "davej@codemonkey.org.uk >> Dave Jones" Subject: Re: rcu, sched: WARNING: CPU: 30 PID: 23771 at kernel/rcu/tree_plugin.h:337 rcu_read_unlock_special+0x369/0x550() References: <20150121025754.GV9719@linux.vnet.ibm.com> <54BFC979.8040107@oracle.com> <20150122004305.GJ9719@linux.vnet.ibm.com> <54C1BFFD.9060707@oracle.com> <20150123035158.GP9719@linux.vnet.ibm.com> <54C1C7D2.906@oracle.com> <54C1C899.8000106@oracle.com> <20150123065542.GQ9719@linux.vnet.ibm.com> <20150123093644.GA11175@linux.vnet.ibm.com> <54C2C278.1000608@oracle.com> <20150123225411.GZ9719@linux.vnet.ibm.com> In-Reply-To: <20150123225411.GZ9719@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/23/2015 05:54 PM, Paul E. McKenney wrote: > On Fri, Jan 23, 2015 at 04:51:52PM -0500, Sasha Levin wrote: >> > On 01/23/2015 04:36 AM, Paul E. McKenney wrote: >>> > > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h >>> > > index 8669de884445..ec99dc16aa38 100644 >>> > > --- a/kernel/rcu/tree_plugin.h >>> > > +++ b/kernel/rcu/tree_plugin.h >>> > > @@ -322,6 +322,7 @@ void rcu_read_unlock_special(struct task_struct *t) >>> > > special = t->rcu_read_unlock_special; >>> > > if (special.b.need_qs) { >>> > > rcu_preempt_qs(); >>> > > + t->rcu_read_unlock_special.need_qs = false; >> > >> > It didn't compile, I've used: >> > >> > t->rcu_read_unlock_special.b.need_qs = false; > Apologies, I should have marked it "untested". Good show on finding > the correct fix. > > But does your fixed version help? ;-) I haven't seen it happening it again, but you won't get a "yes" out of me until tomorrow evening :) Thanks, Sasha