From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756624AbcKKOct (ORCPT ); Fri, 11 Nov 2016 09:32:49 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:45928 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756106AbcKKOcr (ORCPT ); Fri, 11 Nov 2016 09:32:47 -0500 Date: Fri, 11 Nov 2016 06:32:43 -0800 From: Guenter Roeck To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org Subject: RCU related tracebacks in various boot tests in -next Message-ID: <20161111143243.GA13198@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I see a number of RCU related tracebacks in recent versions of -next. The problem was first seen in next-20161109. I didn't bisect, but my wild guess is to blame Paul's related changes. Please let me know if a bisect is needed. Detailed logs are at http://kerneltests.org/builders. Build/test scripts are in the various subdirectories of https://github.com/groeck/linux-build-test/tree/master/rootfs/. Thanks, Guenter -------- arm: [ 1.699096] =============================== [ 1.699188] suspicious RCU usage. ] [ 1.699340] 4.9.0-rc4-next-20161111 #4 Not tainted [ 1.699462] ------------------------------- [ 1.699554] ./include/trace/events/irq.h:69 suspicious rcu_dereference_check() usage! [ 1.699707] [ 1.699707] other info that might help us debug this: [ 1.699707] [ 1.699890] [ 1.699890] RCU used illegally from idle CPU! [ 1.699890] rcu_scheduler_active = 1, debug_locks = 0 [ 1.700103] RCU used illegally from extended quiescent state! [ 1.700256] no locks held by swapper/0/0. [ 1.700317] [ 1.700317] stack backtrace: [ 1.700500] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc4-next-20161111 #4 [ 1.700653] Hardware name: Generic OMAP3 (Flattened Device Tree) [ 1.700988] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 1.701171] [] (show_stack) from [] (dump_stack+0xb0/0xe4) [ 1.701354] [] (dump_stack) from [] (__handle_irq_event_percpu+0x2fc/0x3d0) [ 1.701538] [] (__handle_irq_event_percpu) from [] (handle_irq_event_percpu+0x1c/0x58) [ 1.701751] [] (handle_irq_event_percpu) from [] (handle_irq_event+0x38/0x5c) [ 1.701934] [] (handle_irq_event) from [] (handle_level_irq+0xb8/0x14c) [ 1.702087] [] (handle_level_irq) from [] (generic_handle_irq+0x20/0x34) [ 1.702270] [] (generic_handle_irq) from [] (__handle_domain_irq+0x64/0xe0) [ 1.702453] [] (__handle_domain_irq) from [] (__irq_svc+0x70/0x98) [ 1.702606] [] (__irq_svc) from [] (arch_cpu_idle+0x20/0x3c) [ 1.702789] [] (arch_cpu_idle) from [] (cpu_startup_entry+0x180/0x224) [ 1.702941] [] (cpu_startup_entry) from [] (start_kernel+0x344/0x3b8) [ 1.703186] [] (start_kernel) from [<8000807c>] (0x8000807c) arm64: [ 1.247359] ------------[ cut here ]------------ [ 1.247761] WARNING: CPU: 1 PID: 0 at kernel/rcu/tree.c:380 rcu_momentary_dyntick_idle+0xc0/0xc8 [ 1.247884] Modules linked in: [ 1.247987] [ 1.248150] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.0-rc4-next-20161111 #1 [ 1.248241] Hardware name: ZynqMP EP108 (DT) [ 1.248350] task: ffff80007c4d1900 task.stack: ffff80007c4e0000 [ 1.248445] PC is at rcu_momentary_dyntick_idle+0xc0/0xc8 [ 1.248523] LR is at rcu_note_context_switch+0x1b4/0x2c0 [ 1.248595] pc : [] lr : [] pstate: 600000c5 [ 1.248676] sp : ffff80007c4e3ea0 [ 1.248738] x29: ffff80007c4e3ea0 x28: ffff000008d88000 [ 1.248842] x27: ffff80007c4e0000 x26: ffff000008da4803 [ 1.248919] x25: 0000000000000000 x24: ffff80007c4e0000 [ 1.248992] x23: ffff0000088b3544 x22: ffff80007c4d1900 [ 1.249065] x21: ffff80007efb1880 x20: ffff000008d88000 [ 1.249138] x19: ffff80007c4d1900 x18: 000000000000000e [ 1.249211] x17: 0000000000000007 x16: 0000000000000001 [ 1.249285] x15: 000000000000004c x14: 0000000000000000 [ 1.249362] x13: 000000000000000b x12: 0000000000000006 [ 1.249435] x11: ffff0000088e0ad8 x10: ffff80007efb18b0 [ 1.249586] x9 : ffff0000088e0ad4 x8 : 00000000029f6300 [ 1.249715] x7 : 7fffffffffffffff x6 : ffff80007efabbd0 [ 1.249839] x5 : 0000000000000004 x4 : ffff000008da0688 [ 1.249963] x3 : 0000000000000004 x2 : ffff80007efabbdc [ 1.250088] x1 : 0000000000000001 x0 : ffff000008da4811 [ 1.250213] [ 1.250325] ---[ end trace 2930a57464ba65da ]--- [ 1.250551] Call trace: [ 1.251134] Exception stack(0xffff80007c4e3cd0 to 0xffff80007c4e3e00) [ 1.251396] 3cc0: ffff80007c4d1900 0001000000000000 [ 1.251605] 3ce0: ffff80007c4e3ea0 ffff000008114df0 ffff000008e6c388 ffff80007c4e3f80 [ 1.251790] 3d00: ffff80007c4e3d90 ffff00000838b804 ffff000008e6c3ac ffff80007c4e3fd0 [ 1.251972] 3d20: 00000000ffffffd8 ffff000008910b8c 00000000000003e0 ffff000008b4c1c1 [ 1.252151] 3d40: ffff000008e6c388 ffff80007c4e3fd0 ffff000008b4c1bd ffff000008107264 [ 1.252331] 3d60: ffff80007c4e3d90 ffff00000838b4e0 ffff000008da4811 0000000000000001 [ 1.252509] 3d80: ffff80007efabbdc 0000000000000004 ffff000008da0688 0000000000000004 [ 1.252688] 3da0: ffff80007efabbd0 7fffffffffffffff 00000000029f6300 ffff0000088e0ad4 [ 1.252866] 3dc0: ffff80007efb18b0 ffff0000088e0ad8 0000000000000006 000000000000000b [ 1.253043] 3de0: 0000000000000000 000000000000004c 0000000000000001 0000000000000007 [ 1.253269] [] rcu_momentary_dyntick_idle+0xc0/0xc8 [ 1.253442] [] __schedule+0x68/0x570 [ 1.253598] [] schedule+0x3c/0xa8 [ 1.253726] [] schedule_preempt_disabled+0x20/0x38 [ 1.253884] [] cpu_startup_entry+0xd4/0x1d8 [ 1.254026] [] secondary_start_kernel+0x158/0x198 [ 1.254268] [<00000000008bd1a4>] 0x8bd1a4 s390: =============================== suspicious RCU usage. ] 4.9.0-rc4-next-20161111 #1 Not tainted ------------------------------- ./include/trace/events/rcu.h:454 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! no locks held by swapper/0/0. stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc4-next-20161111 #1 Hardware name: QEMU QEMU QEMU (KVM) Stack: 000000001fffbcb0 000000001fffbd40 0000000000000003 0000000000000000 000000001fffbde0 000000001fffbd58 000000001fffbd58 0000000000000020 0000000001e20b70 ffffffffffffffff 0000000000000000 0404c0010000000a 000000000000000c 000000001fffbda8 0000000000000000 0000000000000000 0000000000000000 00000000001168f4 000000001fffbd40 000000001fffbd88 Call Trace: ([<00000000001167b0>] show_trace+0x100/0x104) [<0000000000116896>] show_stack+0x6e/0xec [<00000000007985e0>] dump_stack+0x94/0xd4 [<000000000021882e>] rcu_eqs_exit_common.isra.49+0x1ee/0x21c [<000000000022172a>] rcu_irq_enter+0x1ca/0x284 [<0000000000182178>] irq_enter+0x40/0xc0 [<000000000010dcca>] do_IRQ+0x5a/0x94 [<0000000000ad234e>] ext_int_handler+0x11e/0x124 [<0000000000103c50>] enabled_wait+0x64/0x110 ([<0000000000103c3c>] enabled_wait+0x50/0x110) [<0000000000103eca>] arch_cpu_idle+0x42/0x54 [<0000000000ad0576>] default_idle_call+0x4e/0x64 [<00000000001ddcb0>] cpuidle_idle_call+0x54/0xa4 [<00000000001dde62>] cpu_startup_entry+0xea/0x12c [<0000000000eaec82>] start_kernel+0x3ee/0x3fc [<0000000000100020>] _stext+0x20/0x80