From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752267AbbCKT6J (ORCPT ); Wed, 11 Mar 2015 15:58:09 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:27299 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbbCKT6G (ORCPT ); Wed, 11 Mar 2015 15:58:06 -0400 Message-ID: <55009E2C.7070100@oracle.com> Date: Wed, 11 Mar 2015 15:57:32 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: "Paul E. McKenney" , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan CC: LKML , Dave Jones Subject: rcu: frequent rcu lockups Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, I've started seeing the following hang pretty often during my fuzzing. The system proceeds to lock up after that. [ 3209.655703] INFO: rcu_preempt detected stalls on CPUs/tasks: [ 3209.655703] Tasks blocked on level-1 rcu_node (CPUs 16-31): [ 3209.655703] (detected by 0, t=30502 jiffies, g=48799, c=48798, q=1730) [ 3209.655703] All QSes seen, last rcu_preempt kthread activity 1 (4295246069-4295246068), jiffies_till_next_fqs=1, root ->qsmask 0x2 [ 3209.655703] trinity-c24 R running task 26944 9338 9110 0x10080000 [ 3209.655703] 0000000000002396 00000000e68fa48e ffff880050607dc8 ffffffffa427679b [ 3209.655703] ffff880050607d98 ffffffffb1b36000 0000000000000001 00000001000440f4 [ 3209.655703] ffffffffb1b351c8 dffffc0000000000 ffff880050622000 ffffffffb1721000 [ 3209.655703] Call Trace: [ 3209.655703] sched_show_task (kernel/sched/core.c:4542) [ 3209.655703] rcu_check_callbacks (kernel/rcu/tree.c:1225 kernel/rcu/tree.c:1331 kernel/rcu/tree.c:3389 kernel/rcu/tree.c:3453 kernel/rcu/tree.c:2683) [ 3209.655703] ? acct_account_cputime (kernel/tsacct.c:168) [ 3209.655703] update_process_times (./arch/x86/include/asm/preempt.h:22 kernel/time/timer.c:1386) [ 3209.655703] tick_periodic (kernel/time/tick-common.c:92) [ 3209.655703] ? tick_handle_periodic (kernel/time/tick-common.c:105) [ 3209.655703] tick_handle_periodic (kernel/time/tick-common.c:105) [ 3209.655703] local_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:891) [ 3209.655703] smp_trace_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:934 include/linux/jump_label.h:114 ./arch/x86/include/asm/trace/irq_vectors.h:45 arch/x86/kernel/apic/apic.c:935) [ 3209.655703] trace_apic_timer_interrupt (arch/x86/kernel/entry_64.S:920) [ 3209.655703] ? add_wait_queue (include/linux/wait.h:116 kernel/sched/wait.c:29) [ 3209.655703] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/paravirt.h:809 include/linux/spinlock_api_smp.h:162 kernel/locking/spinlock.c:191) [ 3209.655703] add_wait_queue (kernel/sched/wait.c:31) [ 3209.655703] do_wait (kernel/exit.c:1473) [ 3209.655703] ? trace_rcu_dyntick (include/trace/events/rcu.h:363 (discriminator 19)) [ 3209.655703] ? wait_consider_task (kernel/exit.c:1465) [ 3209.655703] ? find_get_pid (kernel/pid.c:490) [ 3209.655703] SyS_wait4 (kernel/exit.c:1618 kernel/exit.c:1586) [ 3209.655703] ? perf_syscall_exit (kernel/trace/trace_syscalls.c:549) [ 3209.655703] ? SyS_waitid (kernel/exit.c:1586) [ 3209.655703] ? kill_orphaned_pgrp (kernel/exit.c:1444) [ 3209.655703] ? syscall_trace_enter_phase2 (arch/x86/kernel/ptrace.c:1592) [ 3209.655703] ? trace_hardirqs_on_thunk (arch/x86/lib/thunk_64.S:42) [ 3209.655703] tracesys_phase2 (arch/x86/kernel/entry_64.S:347) Thanks, Sasha