From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753659Ab2IWFj0 (ORCPT ); Sun, 23 Sep 2012 01:39:26 -0400 Received: from mail-we0-f174.google.com ([74.125.82.174]:46442 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753606Ab2IWFjZ (ORCPT ); Sun, 23 Sep 2012 01:39:25 -0400 Message-ID: <505EA09B.6040105@gmail.com> Date: Sun, 23 Sep 2012 07:39:39 +0200 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120913 Thunderbird/15.0.1 MIME-Version: 1.0 To: paulmck@linux.vnet.ibm.com CC: Michael Wang , Dave Jones , "linux-kernel@vger.kernel.org" , fweisbec@gmail.com Subject: Re: RCU idle CPU detection is broken in linux-next References: <20120921121346.GD2458@linux.vnet.ibm.com> <505C6B03.7020305@gmail.com> <20120921151203.GA2454@linux.vnet.ibm.com> <505C855F.3060301@gmail.com> <505D7621.4040505@gmail.com> <20120922150913.GA2934@linux.vnet.ibm.com> <505DDBE7.7010706@gmail.com> <20120922155613.GB2934@linux.vnet.ibm.com> <505DFA65.3080805@gmail.com> <20120922212735.GG2934@linux.vnet.ibm.com> <20120923002105.GA1112@linux.vnet.ibm.com> In-Reply-To: <20120923002105.GA1112@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/23/2012 02:21 AM, Paul E. McKenney wrote: > On Sat, Sep 22, 2012 at 02:27:35PM -0700, Paul E. McKenney wrote: >> On Sat, Sep 22, 2012 at 07:50:29PM +0200, Sasha Levin wrote: >>> On 09/22/2012 05:56 PM, Paul E. McKenney wrote: >>>> And now the prime suspect is the new CONFIG_RCU_USER_QS=y. Do these >>>> warnings ever show up with CONFIG_RCU_USER_QS=n? >>> >>> It seems that disabling that does make the warnings go away. >>> >>> I'll keep the tests running in case it just reduces the chances or something >>> like that. >> >> Thank you for testing this! >> >> And of course the reason that I didn't see these problems is that I >> failed to update my tests to enable CONFIG_RCU_USER_QS. :-/ > > Also the fact that I run 32-bit guests on x86. Sigh! > > I take it that you are running 64-bit guests? Yes, that's correct. Thanks, Sasha