Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753443AbbHEANL (ORCPT ); Tue, 4 Aug 2015 20:13:11 -0400 Received: from arcturus.aphlor.org ([188.246.204.175]:35568 "EHLO arcturus.aphlor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753105AbbHEANJ (ORCPT ); Tue, 4 Aug 2015 20:13:09 -0400 Date: Tue, 4 Aug 2015 20:12:50 -0400 From: Dave Jones To: Sasha Levin Cc: paulmck@linux.vnet.ibm.com, Linux Kernel , Josh Triplett , fweisbec@gmail.com, Peter Zijlstra Subject: Re: 4.2-rc5 rcu stalls. Message-ID: <20150805001250.GA22259@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Sasha Levin , paulmck@linux.vnet.ibm.com, Linux Kernel , Josh Triplett , fweisbec@gmail.com, Peter Zijlstra References: <20150803210835.GA4467@codemonkey.org.uk> <20150803213723.GN27280@linux.vnet.ibm.com> <20150803215535.GA13717@codemonkey.org.uk> <20150803220355.GO27280@linux.vnet.ibm.com> <55C0458B.6080003@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <55C0458B.6080003@oracle.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Score: -2.9 (--) X-Spam-Report: Spam report generated by SpamAssassin on "arcturus.aphlor.org" Content analysis details: (-2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-Authenticated-User: davej@codemonkey.org.uk Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4408 Lines: 73 On Tue, Aug 04, 2015 at 12:54:35AM -0400, Sasha Levin wrote: > On 08/03/2015 06:03 PM, Paul E. McKenney wrote: > >> > Ugh, that doesn't revert cleanly. Got something handy ? > > I do not, but perhaps either Sasha or Frederic do. > > I've attached a revert courtesy of Peter. Thanks. At first I thought this was doing the trick, but then I hit this again. [23643.545873] INFO: rcu_preempt detected stalls on CPUs/tasks: [23643.546031] Tasks blocked on level-0 rcu_node (CPUs 0-3): P31722 [23643.546173] (detected by 3, t=65002 jiffies, g=2256887, c=2256886, q=0) [23643.546326] trinity-watchdo R running task 14336 31722 31721 0x00080000 [23643.546488] ffff8804fcfe7cc8 000000000000ded0 0000000000000002 ffff8804f58bb680 [23643.546661] ffff8800ce4951c0 ffff8804fcfe7cb8 ffff8804fcfe8000 ffff8804f6552608 [23643.546830] 0000000000000009 ffff8804fcfe7e88 0000000000000009 ffff8804fcfe7ce8 [23643.547001] Call Trace: [23643.547058] [] preempt_schedule_common+0x22/0x40 [23643.547201] [] preempt_schedule+0x1f/0x30 [23643.547329] [] ___preempt_schedule+0x12/0x14 [23643.547465] [] ? do_send_sig_info+0x5d/0x80 [23643.547599] [] ? _raw_spin_unlock_irqrestore+0x42/0x70 [23643.547753] [] ? _raw_spin_unlock_irqrestore+0x60/0x70 [23643.547910] [] do_send_sig_info+0x5d/0x80 [23643.548039] [] group_send_sig_info+0xb2/0x120 [23643.548175] [] ? group_send_sig_info+0x5/0x120 [23643.548314] [] ? rcu_read_lock_held+0x4f/0x60 [23643.548451] [] kill_pid_info+0x7f/0x150 [23643.548576] [] ? kill_pid_info+0x20/0x150 [23643.548705] [] SYSC_kill+0xf4/0x2b0 [23643.548821] [] ? SYSC_kill+0x9d/0x2b0 [23643.548942] [] ? trace_hardirqs_on_caller+0x14b/0x1e0 [23643.549097] [] ? trace_hardirqs_on+0xd/0x10 [23643.549231] [] ? context_tracking_user_exit+0x13/0x20 [23643.549387] [] ? syscall_trace_enter_phase1+0xf7/0x150 [23643.549540] [] ? trace_hardirqs_on_thunk+0x17/0x19 [23643.549687] [] SyS_kill+0xe/0x10 [23643.549799] [] entry_SYSCALL_64_fastpath+0x12/0x6f [23643.549946] trinity-watchdo R running task 14336 31722 31721 0x00080000 [23643.550106] ffff8804fcfe7cc8 000000000000ded0 0000000000000002 ffff8804f58bb680 [23643.550276] ffff8800ce4951c0 ffff8804fcfe7cb8 ffff8804fcfe8000 ffff8804f6552608 [23643.550446] 0000000000000009 ffff8804fcfe7e88 0000000000000009 ffff8804fcfe7ce8 [23643.550615] Call Trace: [23643.550668] [] preempt_schedule_common+0x22/0x40 [23643.550809] [] preempt_schedule+0x1f/0x30 [23643.550935] [] ___preempt_schedule+0x12/0x14 [23643.551072] [] ? do_send_sig_info+0x5d/0x80 [23643.551204] [] ? _raw_spin_unlock_irqrestore+0x42/0x70 [23643.551358] [] ? _raw_spin_unlock_irqrestore+0x60/0x70 [23643.551515] [] do_send_sig_info+0x5d/0x80 [23643.551642] [] group_send_sig_info+0xb2/0x120 [23643.551779] [] ? group_send_sig_info+0x5/0x120 [23643.551915] [] ? rcu_read_lock_held+0x4f/0x60 [23643.557757] [] kill_pid_info+0x7f/0x150 [23643.563613] [] ? kill_pid_info+0x20/0x150 [23643.569450] [] SYSC_kill+0xf4/0x2b0 [23643.575270] [] ? SYSC_kill+0x9d/0x2b0 [23643.581025] [] ? trace_hardirqs_on_caller+0x14b/0x1e0 [23643.586867] [] ? trace_hardirqs_on+0xd/0x10 [23643.592620] [] ? context_tracking_user_exit+0x13/0x20 [23643.598317] [] ? syscall_trace_enter_phase1+0xf7/0x150 [23643.603903] [] ? trace_hardirqs_on_thunk+0x17/0x19 [23643.609404] [] SyS_kill+0xe/0x10 [23643.614788] [] entry_SYSCALL_64_fastpath+0x12/0x6f Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/