From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: localed stuck in recent 3.18 git in copy_net_ns? Date: Fri, 24 Oct 2014 11:33:23 -0700 Message-ID: <20141024183323.GX4977@linux.vnet.ibm.com> References: <1414044566.2031.1.camel@declera.com> <20141023122750.GP4977@linux.vnet.ibm.com> <20141023153333.GA19278@linux.vnet.ibm.com> <20141023195159.GA2331@declera.com> <20141023200507.GC4977@linux.vnet.ibm.com> <1414100740.2065.2.camel@declera.com> <20141023220406.GJ4977@linux.vnet.ibm.com> <31920.1414126114@famine> <20141024145028.GN4977@linux.vnet.ibm.com> <5677.1414174811@famine> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Yanko Kaneti , Josh Boyer , "Eric W. Biederman" , Cong Wang , Kevin Fenzi , netdev , "Linux-Kernel@Vger. Kernel. Org" To: Jay Vosburgh Return-path: Content-Disposition: inline In-Reply-To: <5677.1414174811@famine> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, Oct 24, 2014 at 11:20:11AM -0700, Jay Vosburgh wrote: > Paul E. McKenney wrote: > > >On Thu, Oct 23, 2014 at 09:48:34PM -0700, Jay Vosburgh wrote: > >> Paul E. McKenney wrote: > [...] > >> >Either way, my patch assumed that 39953dfd4007 (rcu: Avoid misordering in > >> >__call_rcu_nocb_enqueue()) would work and that 1772947bd012 (rcu: Handle > >> >NOCB callbacks from irq-disabled idle code) would fail. Is that the case? > >> >If not, could you please bisect the commits between 11ed7f934cb8 (rcu: > >> >Make nocb leader kthreads process pending callbacks after spawning) > >> >and c847f14217d5 (rcu: Avoid misordering in nocb_leader_wait())? > >> > >> Just a note to add that I am also reliably inducing what appears > >> to be this issue on a current -net tree, when configuring openvswitch > >> via script. I am available to test patches or bisect tomorrow (Friday) > >> US time if needed. > > > >Thank you, Jay! Could you please check to see if reverting this commit > >fixes things for you? > > > >35ce7f29a44a rcu: Create rcuo kthreads only for onlined CPUs > > > >Reverting is not a long-term fix, as this commit is itself a bug fix, > >but would be good to check to see if you are seeing the same thing that > >Yanko is. ;-) > > Just to confirm what Yanko found, reverting this commit makes > the problem go away for me. Thank you! I take it that the patches that don't help Yanko also don't help you? Thanx, Paul