From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757399AbbE3BD6 (ORCPT ); Fri, 29 May 2015 21:03:58 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:28912 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751420AbbE3BDt (ORCPT ); Fri, 29 May 2015 21:03:49 -0400 Message-ID: <55690C48.1060003@oracle.com> Date: Fri, 29 May 2015 21:03:04 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, tglx@linutronix.de, peterz@infradead.org, hpa@zytor.com, mingo@kernel.org, linux-tip-commits@vger.kernel.org Subject: Re: [tip:sched/core] sched/core: Validate rq_clock*() serialization References: <20150105103554.361872747@infradead.org> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/14/2015 09:03 AM, tip-bot for Peter Zijlstra wrote: > Commit-ID: cebde6d681aa45f96111cfcffc1544cf2a0454ff > Gitweb: http://git.kernel.org/tip/cebde6d681aa45f96111cfcffc1544cf2a0454ff > Author: Peter Zijlstra > AuthorDate: Mon, 5 Jan 2015 11:18:10 +0100 > Committer: Ingo Molnar > CommitDate: Wed, 14 Jan 2015 13:34:19 +0100 > > sched/core: Validate rq_clock*() serialization > > rq->clock{,_task} are serialized by rq->lock, verify this. > > One immediate fail is the usage in scale_rt_capability, so 'annotate' > that for now, there's more 'funny' there. Maybe change rq->lock into a > raw_seqlock_t? > > (Only 32-bit is affected) > > Signed-off-by: Peter Zijlstra (Intel) > Link: http://lkml.kernel.org/r/20150105103554.361872747@infradead.org > Cc: Linus Torvalds > Cc: umgwanakikbuti@gmail.com > Signed-off-by: Ingo Molnar > --- Hey Peter, I'm seeing the following in the latest -next: [ 2706.857941] ------------[ cut here ]------------ [ 2706.857963] WARNING: CPU: 6 PID: 14780 at kernel/sched/sched.h:728 update_curr+0x3db/0x550() [ 2706.857971] Modules linked in: [ 2706.857982] CPU: 6 PID: 14780 Comm: trinity-c2 Not tainted 4.1.0-rc5-next-20150529-sasha-00039-g7fd455d-dirty #2262 [ 2706.858000] ffffffffa6a1426a 00000000c9f98986 ffff8802b6807b98 ffffffffa6a1426a [ 2706.858015] 0000000000000000 0000000000000000 ffff8802b6807be8 ffffffff9d1e50c6 [ 2706.858029] ffffffff9d1e52f5 ffffffff9d28a2fb ffff8800c3d0b068 ffff88050c1c3068 [ 2706.858033] Call Trace: [ 2706.858054] ? dump_stack (lib/dump_stack.c:52) [ 2706.858064] dump_stack (lib/dump_stack.c:52) [ 2706.858077] warn_slowpath_common (kernel/panic.c:448) [ 2706.858085] ? warn_slowpath_null (kernel/panic.c:479) [ 2706.858092] ? update_curr (kernel/sched/sched.h:728 kernel/sched/fair.c:698) [ 2706.858102] warn_slowpath_null (kernel/panic.c:482) [ 2706.858110] update_curr (kernel/sched/sched.h:728 kernel/sched/fair.c:698) [ 2706.858116] ? update_curr (kernel/sched/fair.c:697) [ 2706.858128] task_tick_fair (include/linux/sched.h:3049 kernel/sched/fair.c:397 kernel/sched/fair.c:2795 kernel/sched/fair.c:3372 kernel/sched/fair.c:8000) [ 2706.858141] ? sched_clock_cpu (kernel/sched/clock.c:315) [ 2706.858151] ? task_tick_fair (kernel/sched/fair.c:7994) [ 2706.858162] scheduler_tick (kernel/sched/core.c:2523) [ 2706.858177] update_process_times (kernel/time/timer.c:1399) [ 2706.858188] tick_sched_handle.isra.12 (kernel/time/tick-sched.c:152) [ 2706.858196] ? tick_sched_handle.isra.12 (kernel/time/tick-sched.c:134) [ 2706.858206] tick_sched_timer (kernel/time/tick-sched.c:1075) [ 2706.858217] __hrtimer_run_queues (kernel/time/hrtimer.c:1138 kernel/time/hrtimer.c:1194) [ 2706.858228] ? ftrace_call (arch/x86/kernel/mcount_64.S:158) [ 2706.858237] ? tick_sched_do_timer (kernel/time/tick-sched.c:1059) [ 2706.858246] ? hrtimer_fixup_init (kernel/time/hrtimer.c:1161) [ 2706.858256] ? __hrtimer_run_queues (kernel/time/hrtimer.c:1161) [ 2706.858267] hrtimer_interrupt (kernel/time/hrtimer.c:1231) [ 2706.858281] ? preempt_schedule_context (kernel/sched/core.c:2941 (discriminator 1) include/linux/jump_label.h:125 (discriminator 1) include/linux/context_tracking_state.h:29 (discriminator 1) include/linux/context_tracking.h:34 (discriminator 1) kernel/sched/core.c:2947 (discriminator 1)) [ 2706.858293] local_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:891) [ 2706.858301] ? local_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:863) [ 2706.858311] smp_apic_timer_interrupt (./arch/x86/include/asm/apic.h:655 arch/x86/kernel/apic/apic.c:915) [ 2706.858323] apic_timer_interrupt (arch/x86/kernel/entry_64.S:911) [ 2706.858332] [ 2706.858333] ---[ end trace b7e04749c55c3d4e ]--- Thanks, Sasha