From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: linux-next: Tree for Feb 4 Date: Thu, 5 Feb 2015 10:45:37 -0800 Message-ID: <20150205184537.GJ5370@linux.vnet.ibm.com> References: <20150205005716.GS5370@linux.vnet.ibm.com> <20150205015144.GT5370@linux.vnet.ibm.com> <54D3186F.7030500@sr71.net> <20150205130343.6ac0eda9@gandalf.local.home> <20150205130802.289a8be0@gandalf.local.home> <54D3B253.3050000@sr71.net> <20150205183412.GI5370@linux.vnet.ibm.com> <54D3B7F5.9070209@sr71.net> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <54D3B7F5.9070209@sr71.net> Sender: linux-kernel-owner@vger.kernel.org To: Dave Hansen Cc: Steven Rostedt , sedat.dilek@gmail.com, "Rafael J. Wysocki" , "Rafael J. Wysocki" , linux-next , LKML , Stephen Rothwell , Kristen Carlson Accardi , "H. Peter Anvin" , Rik van Riel , Mel Gorman List-Id: linux-next.vger.kernel.org On Thu, Feb 05, 2015 at 10:35:33AM -0800, Dave Hansen wrote: > On 02/05/2015 10:34 AM, Paul E. McKenney wrote: > >> > Did I actually need to be > >> > onlining/offlining CPUs to hit the splat that Sedat was reporting? > > Yep, you do need to offline at least one CPU to hit that splat. > > Heh, do we need a debugging mode that will randomly offline/online CPUs? :) For that, kernel/rcu/rcutorture.c and kernel/locking/locktorture.c are your friends. ;-) The problem is that I only run RCU-relevant combinations of Kconfigs, which means that I missed the ones that Sedat used to find this problem. So I guess it is a good thing that others run -next testing. Thanx, Paul