From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jay Vosburgh Subject: Re: localed stuck in recent 3.18 git in copy_net_ns? Date: Fri, 24 Oct 2014 11:20:11 -0700 Message-ID: <5677.1414174811@famine> References: <20141022224032.GA1240@declera.com> <20141022232421.GN4977@linux.vnet.ibm.com> <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> Cc: Yanko Kaneti , Josh Boyer , "Eric W. Biederman" , Cong Wang , Kevin Fenzi , netdev , "Linux-Kernel@Vger. Kernel. Org" To: paulmck@linux.vnet.ibm.com Return-path: In-reply-to: <20141024145028.GN4977@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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. -J --- -Jay Vosburgh, jay.vosburgh@canonical.com