From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4B99C6778C for ; Thu, 5 Jul 2018 08:58:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6178721A02 for ; Thu, 5 Jul 2018 08:58:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6178721A02 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753469AbeGEI6i (ORCPT ); Thu, 5 Jul 2018 04:58:38 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:46410 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752458AbeGEI6h (ORCPT ); Thu, 5 Jul 2018 04:58:37 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0647118A; Thu, 5 Jul 2018 01:58:37 -0700 (PDT) Received: from [0.0.0.0] (e107985-lin.cambridge.arm.com [10.1.210.41]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 797313F5AD; Thu, 5 Jul 2018 01:58:35 -0700 (PDT) Subject: Re: [lkp-robot] [sched/fair] fbd5188493: WARNING:inconsistent_lock_state To: kernel test robot , Matt Fleming Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Ingo Molnar , Mike Galbraith , lkp@01.org References: <20180705080227.GH23907@yexl-desktop> From: Dietmar Eggemann Message-ID: <0ac4845e-cf6b-c5e3-a16c-f2fc457c5ef5@arm.com> Date: Thu, 5 Jul 2018 10:58:33 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180705080227.GH23907@yexl-desktop> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 07/05/2018 10:02 AM, kernel test robot wrote: > > FYI, we noticed the following commit (built with gcc-7): > > commit: fbd51884933192c9cada60628892024495942482 ("[PATCH] sched/fair: Avoid divide by zero when rebalancing domains") > url: https://github.com/0day-ci/linux/commits/Matt-Fleming/sched-fair-Avoid-divide-by-zero-when-rebalancing-domains/20180705-024633 > > > in testcase: trinity > with following parameters: > > runtime: 300s > > test-description: Trinity is a linux system call fuzz tester. > test-url: http://codemonkey.org.uk/projects/trinity/ > > > on test machine: qemu-system-x86_64 -enable-kvm -cpu host -smp 2 -m 1G [...] > [ 0.335612] WARNING: inconsistent lock state I get the same on arm64 (juno r0) during boot consistently: [ 1.458414] ================================ [ 1.462641] WARNING: inconsistent lock state [ 1.466870] 4.18.0-rc3-00016-g1b05c8317958 #2 Not tainted [ 1.472215] -------------------------------- [ 1.476440] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ 1.482389] rcu_preempt/10 [HC0[0]:SC0[0]:HE1:SE1] takes: [ 1.487733] (____ptrval____) (&rq->lock){?.-.}, at: pick_next_task_fair+0x234/0x8e8 [ 1.495342] {IN-HARDIRQ-W} state was registered at: [ 1.500174] lock_acquire+0xc8/0x290 [ 1.503802] _raw_spin_lock+0x44/0x58 [ 1.507517] scheduler_tick+0x5c/0x118 [ 1.511316] update_process_times+0x48/0x60 [ 1.515545] tick_periodic+0x50/0x108 [ 1.519256] tick_handle_periodic+0x38/0xa8 [ 1.523485] arch_timer_handler_phys+0x3c/0x50 [ 1.527973] handle_percpu_devid_irq+0xcc/0x4a0 [ 1.532543] generic_handle_irq+0x34/0x50 [ 1.536598] __handle_domain_irq+0x68/0xc0 [ 1.540738] gic_handle_irq+0x60/0xb8 [ 1.544448] el1_irq+0xb4/0x130 [ 1.547644] start_kernel+0x34c/0x490 [ 1.551353] irq event stamp: 1601 [ 1.554637] hardirqs last enabled at (1601): [] _raw_spin_unlock_irqrestore+0x74/0xa8 [ 1.564026] hardirqs last disabled at (1600): [] _raw_spin_lock_irqsave+0x2c/0x70 [ 1.572986] softirqs last enabled at (0): [] copy_process.isra.4.part.5+0x430/0x18f0 [ 1.582285] softirqs last disabled at (0): [<0000000000000000>] (null) [ 1.589606] [ 1.589606] other info that might help us debug this: [ 1.596067] Possible unsafe locking scenario: [ 1.596067] [ 1.601926] CPU0 [ 1.604344] ---- [ 1.606761] lock(&rq->lock); [ 1.609788] [ 1.612377] lock(&rq->lock); [ 1.615576] [ 1.615576] *** DEADLOCK *** [ 1.615576] [ 1.621438] no locks held by rcu_preempt/10. [ 1.625661] [ 1.625661] stack backtrace: [ 1.629977] CPU: 2 PID: 10 Comm: rcu_preempt Not tainted 4.18.0-rc3-00016-g1b05c8317958 #2 [ 1.638160] Hardware name: ARM Juno development board (r0) (DT) [ 1.644018] Call trace: [ 1.646439] dump_backtrace+0x0/0x170 [ 1.650063] show_stack+0x24/0x30 [ 1.653345] dump_stack+0xac/0xe4 [ 1.656625] print_usage_bug+0x208/0x2a8 [ 1.660506] mark_lock+0x5c0/0x668 [ 1.663871] __lock_acquire+0x550/0x1990 [ 1.667752] lock_acquire+0xc8/0x290 [ 1.671290] _raw_spin_lock+0x44/0x58 [ 1.674914] pick_next_task_fair+0x234/0x8e8 [ 1.679142] __schedule+0x160/0xc40 [ 1.682595] schedule+0x50/0xc0 [ 1.685702] schedule_timeout+0x1f4/0x568 [ 1.689673] rcu_gp_kthread+0x4fc/0x860 [ 1.693470] kthread+0x100/0x130 [ 1.696664] ret_from_fork+0x10/0x1c