From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756729AbaCEBRM (ORCPT ); Tue, 4 Mar 2014 20:17:12 -0500 Received: from mail-pa0-f47.google.com ([209.85.220.47]:51636 "EHLO mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756643AbaCEBRI (ORCPT ); Tue, 4 Mar 2014 20:17:08 -0500 MIME-Version: 1.0 In-Reply-To: References: <1393980534.26794.147.camel@edumazet-glaptop2.roam.corp.google.com> From: Florian Fainelli Date: Tue, 4 Mar 2014 17:16:27 -0800 Message-ID: Subject: Re: RCU stalls when running out of memory on 3.14-rc4 w/ NFS and kernel threads priorities changed To: Eric Dumazet Cc: "linux-kernel@vger.kernel.org" , linux-mm , paulmck , linux-nfs , "trond.myklebust" , netdev Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-03-04 17:03 GMT-08:00 Florian Fainelli : > 2014-03-04 16:48 GMT-08:00 Eric Dumazet : >> On Tue, 2014-03-04 at 15:55 -0800, Florian Fainelli wrote: >>> Hi all, >>> >>> I am seeing the following RCU stalls messages appearing on an ARMv7 >>> 4xCPUs system running 3.14-rc4: >>> >>> [ 42.974327] INFO: rcu_sched detected stalls on CPUs/tasks: >>> [ 42.979839] (detected by 0, t=2102 jiffies, g=4294967082, >>> c=4294967081, q=516) >>> [ 42.987169] INFO: Stall ended before state dump start >>> >>> this is happening under the following conditions: >>> >>> - the attached bumper.c binary alters various kernel thread priorities >>> based on the contents of bumpup.cfg and >>> - malloc_crazy is running from a NFS share >>> - malloc_crazy.c is running in a loop allocating chunks of memory but >>> never freeing it >>> >>> when the priorities are altered, instead of getting the OOM killer to >>> be invoked, the RCU stalls are happening. Taking NFS out of the >>> equation does not allow me to reproduce the problem even with the >>> priorities altered. >>> >>> This "problem" seems to have been there for quite a while now since I >>> was able to get 3.8.13 to trigger that bug as well, with a slightly >>> more detailed RCU debugging trace which points the finger at kswapd0. >>> >>> You should be able to get that reproduced under QEMU with the >>> Versatile Express platform emulating a Cortex A15 CPU and the attached >>> files. >>> >>> Any help or suggestions would be greatly appreciated. Thanks! >> >> Do you have a more complete trace, including stack traces ? > > Attatched is what I get out of SysRq-t, which is the only thing I have > (note that the kernel is built with CONFIG_RCU_CPU_STALL_INFO=y): QEMU for Versatile Express w/ 2 CPUs yields something slightly different than the real HW platform this is happening with, but it does produce the RCU stall anyway: [ 125.762946] BUG: soft lockup - CPU#1 stuck for 53s! [malloc_crazy:91] [ 125.766841] Modules linked in: [ 125.768389] [ 125.769199] CPU: 1 PID: 91 Comm: malloc_crazy Not tainted 3.14.0-rc4 #39 [ 125.769883] task: edbded00 ti: c089c000 task.ti: c089c000 [ 125.771743] PC is at load_balance+0x4b0/0x760 [ 125.772069] LR is at cpumask_next_and+0x44/0x5c [ 125.772387] pc : [] lr : [] psr: 60000113 [ 125.772387] sp : c089db48 ip : 80000113 fp : edfd8cf4 [ 125.773128] r10: c0de871c r9 : ed893840 r8 : 00000000 [ 125.773452] r7 : c0de8458 r6 : edfd8840 r5 : edfd8840 r4 : ed89389c [ 125.773825] r3 : 000012d8 r2 : 80000113 r1 : 00000023 r0 : 00000000 [ 125.774332] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 125.774753] Control: 30c7387d Table: 80835d40 DAC: 00000000 [ 125.775266] CPU: 1 PID: 91 Comm: malloc_test_bcm Not tainted 3.14.0-rc4 #39 [ 125.776392] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 125.777026] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 125.777429] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 125.777865] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 125.778333] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 125.778814] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 125.779297] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 125.779734] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 125.780145] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 125.780513] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.780867] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.781312] Exception stack(0xc089db00 to 0xc089db48) [ 125.781787] db00: 00000000 00000023 80000113 000012d8 ed89389c edfd8840 edfd8840 c0de8458 [ 125.782234] db20: 00000000 ed893840 c0de871c edfd8cf4 80000113 c089db48 c01db940 c004ff58 [ 125.782594] db40: 60000113 ffffffff [ 125.782864] [] (__irq_svc) from [] (load_balance+0x4b0/0x760) [ 125.783215] [] (load_balance) from [] (rebalance_domains+0x154/0x284) [ 125.783595] [] (rebalance_domains) from [] (run_rebalance_domains+0x34/0x164) [ 125.784000] [] (run_rebalance_domains) from [] (__do_softirq+0x110/0x24c) [ 125.784388] [] (__do_softirq) from [] (irq_exit+0xac/0xf4) [ 125.784726] [] (irq_exit) from [] (handle_IRQ+0x44/0x90) [ 125.785059] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.785412] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.785742] Exception stack(0xc089dcf8 to 0xc089dd40) [ 125.785983] dce0: ee4e38c0 00000000 [ 125.786360] dd00: 000200da 00000001 ee4e38a0 c0de2340 2d201000 edfe3358 c05c0c18 00000001 [ 125.786737] dd20: c05c0c2c c0e1e180 00000000 c089dd40 c0086050 c0086140 40000113 ffffffff [ 125.787120] [] (__irq_svc) from [] (get_page_from_freelist+0x2bc/0x638) [ 125.787507] [] (get_page_from_freelist) from [] (__alloc_pages_nodemask+0x114/0x8f4) [ 125.787949] [] (__alloc_pages_nodemask) from [] (handle_mm_fault+0x9f8/0xcdc) [ 125.788357] [] (handle_mm_fault) from [] (do_page_fault+0x194/0x27c) [ 125.788726] [] (do_page_fault) from [] (do_DataAbort+0x30/0x90) [ 125.789080] [] (do_DataAbort) from [] (__dabt_usr+0x34/0x40) [ 125.789403] Exception stack(0xc089dfb0 to 0xc089dff8) [ 125.789652] dfa0: ae55e008 11111111 000dc000 ae582000 [ 125.790029] dfc0: be967d18 00000000 00008390 00000000 00000000 00000000 b6f29000 be967d04 [ 125.790404] dfe0: 11111111 be967ce8 00008550 b6e5ce48 20000010 ffffffff [ 125.791282] BUG: soft lockup - CPU#0 stuck for 53s! [kworker/0:1:41] [ 125.791710] Modules linked in: [ 125.792046] [ 125.792836] CPU: 0 PID: 41 Comm: kworker/0:1 Not tainted 3.14.0-rc4 #39 [ 125.793832] task: ed893840 ti: c0826000 task.ti: c0826000 [ 125.795257] PC is at finish_task_switch+0x40/0xec [ 125.795562] LR is at __schedule+0x1fc/0x51c [ 125.795856] pc : [] lr : [] psr: 600f0013 [ 125.795856] sp : c0827ec8 ip : 00000000 fp : c0827edc [ 125.796416] r10: eda56e00 r9 : c0deac28 r8 : 00000000 [ 125.796698] r7 : c0de871c r6 : c0826020 r5 : ed893840 r4 : 00000001 [ 125.797028] r3 : eda56e00 r2 : 000012d7 r1 : ed854780 r0 : edfd8840 [ 125.797488] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 125.797866] Control: 30c7387d Table: 808353c0 DAC: fffffffd [ 125.798321] CPU: 0 PID: 41 Comm: kworker/0:1 Not tainted 3.14.0-rc4 #39 [ 125.800604] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 125.801205] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 125.801786] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 125.802238] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 125.802679] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 125.803108] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 125.803530] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 125.803965] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 125.804380] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 125.804774] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.805181] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.805706] Exception stack(0xc0827e80 to 0xc0827ec8) [ 125.806185] 7e80: edfd8840 ed854780 000012d7 eda56e00 00000001 ed893840 c0826020 c0de871c [ 125.806623] 7ea0: 00000000 c0deac28 eda56e00 c0827edc 00000000 c0827ec8 c04c3274 c0044724 [ 125.807032] 7ec0: 600f0013 ffffffff [ 125.807328] [] (__irq_svc) from [] (finish_task_switch+0x40/0xec) [ 125.807752] [] (finish_task_switch) from [] (__schedule+0x1fc/0x51c) [ 125.808175] [] (__schedule) from [] (worker_thread+0x210/0x404) [ 125.808570] [] (worker_thread) from [] (kthread+0xd4/0xec) [ 125.808952] [] (kthread) from [] (ret_from_fork+0x14/0x3c) [ 246.080014] INFO: rcu_sched detected stalls on CPUs/tasks: [ 246.080611] (detected by 0, t=6972 jiffies, g=4294967160, c=4294967159, q=127) [ 246.081576] INFO: Stall ended before state dump start [ 246.082510] BUG: soft lockup - CPU#1 stuck for 69s! [grep:93] [ 246.082849] Modules linked in: [ 246.083046] [ 246.083179] CPU: 1 PID: 93 Comm: grep Not tainted 3.14.0-rc4 #39 [ 246.083548] task: edbdf480 ti: c09e6000 task.ti: c09e6000 [ 246.083897] PC is at rebalance_domains+0x0/0x284 [ 246.084154] LR is at run_rebalance_domains+0x34/0x164 [ 246.084430] pc : [] lr : [] psr: 20000113 [ 246.084430] sp : c09e7ef8 ip : c0dde340 fp : 40000005 [ 246.084992] r10: 00000007 r9 : c0ddf840 r8 : c0ddf840 [ 246.085267] r7 : edfe0840 r6 : 00000100 r5 : c0de209c r4 : 00000001 [ 246.085606] r3 : c005048c r2 : 2d201000 r1 : 00000001 r0 : edfe0840 [ 246.085944] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 246.086315] Control: 30c7387d Table: 808351c0 DAC: 00000000 [ 246.086626] CPU: 1 PID: 93 Comm: grep Not tainted 3.14.0-rc4 #39 [ 246.086992] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 246.087420] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 246.087825] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 246.088260] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 246.088726] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 246.089190] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 246.089670] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 246.090155] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 246.090822] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 246.091233] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 246.091631] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 246.092007] Exception stack(0xc09e7eb0 to 0xc09e7ef8) [ 246.092291] 7ea0: edfe0840 00000001 2d201000 c005048c [ 246.092719] 7ec0: 00000001 c0de209c 00000100 edfe0840 c0ddf840 c0ddf840 00000007 40000005 [ 246.093142] 7ee0: c0dde340 c09e7ef8 c00504c0 c0050208 20000113 ffffffff [ 246.093647] [] (__irq_svc) from [] (rebalance_domains+0x0/0x284) [ 246.094422] [] (rebalance_domains) from [] (0xc09e6028) From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: RCU stalls when running out of memory on 3.14-rc4 w/ NFS and kernel threads priorities changed Date: Tue, 4 Mar 2014 17:16:27 -0800 Message-ID: References: <1393980534.26794.147.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: "linux-kernel@vger.kernel.org" , linux-mm , paulmck , linux-nfs , "trond.myklebust" , netdev To: Eric Dumazet Return-path: In-Reply-To: Sender: owner-linux-mm@kvack.org List-Id: netdev.vger.kernel.org 2014-03-04 17:03 GMT-08:00 Florian Fainelli : > 2014-03-04 16:48 GMT-08:00 Eric Dumazet : >> On Tue, 2014-03-04 at 15:55 -0800, Florian Fainelli wrote: >>> Hi all, >>> >>> I am seeing the following RCU stalls messages appearing on an ARMv7 >>> 4xCPUs system running 3.14-rc4: >>> >>> [ 42.974327] INFO: rcu_sched detected stalls on CPUs/tasks: >>> [ 42.979839] (detected by 0, t=2102 jiffies, g=4294967082, >>> c=4294967081, q=516) >>> [ 42.987169] INFO: Stall ended before state dump start >>> >>> this is happening under the following conditions: >>> >>> - the attached bumper.c binary alters various kernel thread priorities >>> based on the contents of bumpup.cfg and >>> - malloc_crazy is running from a NFS share >>> - malloc_crazy.c is running in a loop allocating chunks of memory but >>> never freeing it >>> >>> when the priorities are altered, instead of getting the OOM killer to >>> be invoked, the RCU stalls are happening. Taking NFS out of the >>> equation does not allow me to reproduce the problem even with the >>> priorities altered. >>> >>> This "problem" seems to have been there for quite a while now since I >>> was able to get 3.8.13 to trigger that bug as well, with a slightly >>> more detailed RCU debugging trace which points the finger at kswapd0. >>> >>> You should be able to get that reproduced under QEMU with the >>> Versatile Express platform emulating a Cortex A15 CPU and the attached >>> files. >>> >>> Any help or suggestions would be greatly appreciated. Thanks! >> >> Do you have a more complete trace, including stack traces ? > > Attatched is what I get out of SysRq-t, which is the only thing I have > (note that the kernel is built with CONFIG_RCU_CPU_STALL_INFO=y): QEMU for Versatile Express w/ 2 CPUs yields something slightly different than the real HW platform this is happening with, but it does produce the RCU stall anyway: [ 125.762946] BUG: soft lockup - CPU#1 stuck for 53s! [malloc_crazy:91] [ 125.766841] Modules linked in: [ 125.768389] [ 125.769199] CPU: 1 PID: 91 Comm: malloc_crazy Not tainted 3.14.0-rc4 #39 [ 125.769883] task: edbded00 ti: c089c000 task.ti: c089c000 [ 125.771743] PC is at load_balance+0x4b0/0x760 [ 125.772069] LR is at cpumask_next_and+0x44/0x5c [ 125.772387] pc : [] lr : [] psr: 60000113 [ 125.772387] sp : c089db48 ip : 80000113 fp : edfd8cf4 [ 125.773128] r10: c0de871c r9 : ed893840 r8 : 00000000 [ 125.773452] r7 : c0de8458 r6 : edfd8840 r5 : edfd8840 r4 : ed89389c [ 125.773825] r3 : 000012d8 r2 : 80000113 r1 : 00000023 r0 : 00000000 [ 125.774332] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 125.774753] Control: 30c7387d Table: 80835d40 DAC: 00000000 [ 125.775266] CPU: 1 PID: 91 Comm: malloc_test_bcm Not tainted 3.14.0-rc4 #39 [ 125.776392] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 125.777026] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 125.777429] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 125.777865] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 125.778333] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 125.778814] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 125.779297] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 125.779734] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 125.780145] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 125.780513] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.780867] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.781312] Exception stack(0xc089db00 to 0xc089db48) [ 125.781787] db00: 00000000 00000023 80000113 000012d8 ed89389c edfd8840 edfd8840 c0de8458 [ 125.782234] db20: 00000000 ed893840 c0de871c edfd8cf4 80000113 c089db48 c01db940 c004ff58 [ 125.782594] db40: 60000113 ffffffff [ 125.782864] [] (__irq_svc) from [] (load_balance+0x4b0/0x760) [ 125.783215] [] (load_balance) from [] (rebalance_domains+0x154/0x284) [ 125.783595] [] (rebalance_domains) from [] (run_rebalance_domains+0x34/0x164) [ 125.784000] [] (run_rebalance_domains) from [] (__do_softirq+0x110/0x24c) [ 125.784388] [] (__do_softirq) from [] (irq_exit+0xac/0xf4) [ 125.784726] [] (irq_exit) from [] (handle_IRQ+0x44/0x90) [ 125.785059] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.785412] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.785742] Exception stack(0xc089dcf8 to 0xc089dd40) [ 125.785983] dce0: ee4e38c0 00000000 [ 125.786360] dd00: 000200da 00000001 ee4e38a0 c0de2340 2d201000 edfe3358 c05c0c18 00000001 [ 125.786737] dd20: c05c0c2c c0e1e180 00000000 c089dd40 c0086050 c0086140 40000113 ffffffff [ 125.787120] [] (__irq_svc) from [] (get_page_from_freelist+0x2bc/0x638) [ 125.787507] [] (get_page_from_freelist) from [] (__alloc_pages_nodemask+0x114/0x8f4) [ 125.787949] [] (__alloc_pages_nodemask) from [] (handle_mm_fault+0x9f8/0xcdc) [ 125.788357] [] (handle_mm_fault) from [] (do_page_fault+0x194/0x27c) [ 125.788726] [] (do_page_fault) from [] (do_DataAbort+0x30/0x90) [ 125.789080] [] (do_DataAbort) from [] (__dabt_usr+0x34/0x40) [ 125.789403] Exception stack(0xc089dfb0 to 0xc089dff8) [ 125.789652] dfa0: ae55e008 11111111 000dc000 ae582000 [ 125.790029] dfc0: be967d18 00000000 00008390 00000000 00000000 00000000 b6f29000 be967d04 [ 125.790404] dfe0: 11111111 be967ce8 00008550 b6e5ce48 20000010 ffffffff [ 125.791282] BUG: soft lockup - CPU#0 stuck for 53s! [kworker/0:1:41] [ 125.791710] Modules linked in: [ 125.792046] [ 125.792836] CPU: 0 PID: 41 Comm: kworker/0:1 Not tainted 3.14.0-rc4 #39 [ 125.793832] task: ed893840 ti: c0826000 task.ti: c0826000 [ 125.795257] PC is at finish_task_switch+0x40/0xec [ 125.795562] LR is at __schedule+0x1fc/0x51c [ 125.795856] pc : [] lr : [] psr: 600f0013 [ 125.795856] sp : c0827ec8 ip : 00000000 fp : c0827edc [ 125.796416] r10: eda56e00 r9 : c0deac28 r8 : 00000000 [ 125.796698] r7 : c0de871c r6 : c0826020 r5 : ed893840 r4 : 00000001 [ 125.797028] r3 : eda56e00 r2 : 000012d7 r1 : ed854780 r0 : edfd8840 [ 125.797488] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 125.797866] Control: 30c7387d Table: 808353c0 DAC: fffffffd [ 125.798321] CPU: 0 PID: 41 Comm: kworker/0:1 Not tainted 3.14.0-rc4 #39 [ 125.800604] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 125.801205] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 125.801786] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 125.802238] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 125.802679] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 125.803108] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 125.803530] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 125.803965] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 125.804380] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 125.804774] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 125.805181] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 125.805706] Exception stack(0xc0827e80 to 0xc0827ec8) [ 125.806185] 7e80: edfd8840 ed854780 000012d7 eda56e00 00000001 ed893840 c0826020 c0de871c [ 125.806623] 7ea0: 00000000 c0deac28 eda56e00 c0827edc 00000000 c0827ec8 c04c3274 c0044724 [ 125.807032] 7ec0: 600f0013 ffffffff [ 125.807328] [] (__irq_svc) from [] (finish_task_switch+0x40/0xec) [ 125.807752] [] (finish_task_switch) from [] (__schedule+0x1fc/0x51c) [ 125.808175] [] (__schedule) from [] (worker_thread+0x210/0x404) [ 125.808570] [] (worker_thread) from [] (kthread+0xd4/0xec) [ 125.808952] [] (kthread) from [] (ret_from_fork+0x14/0x3c) [ 246.080014] INFO: rcu_sched detected stalls on CPUs/tasks: [ 246.080611] (detected by 0, t=6972 jiffies, g=4294967160, c=4294967159, q=127) [ 246.081576] INFO: Stall ended before state dump start [ 246.082510] BUG: soft lockup - CPU#1 stuck for 69s! [grep:93] [ 246.082849] Modules linked in: [ 246.083046] [ 246.083179] CPU: 1 PID: 93 Comm: grep Not tainted 3.14.0-rc4 #39 [ 246.083548] task: edbdf480 ti: c09e6000 task.ti: c09e6000 [ 246.083897] PC is at rebalance_domains+0x0/0x284 [ 246.084154] LR is at run_rebalance_domains+0x34/0x164 [ 246.084430] pc : [] lr : [] psr: 20000113 [ 246.084430] sp : c09e7ef8 ip : c0dde340 fp : 40000005 [ 246.084992] r10: 00000007 r9 : c0ddf840 r8 : c0ddf840 [ 246.085267] r7 : edfe0840 r6 : 00000100 r5 : c0de209c r4 : 00000001 [ 246.085606] r3 : c005048c r2 : 2d201000 r1 : 00000001 r0 : edfe0840 [ 246.085944] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 246.086315] Control: 30c7387d Table: 808351c0 DAC: 00000000 [ 246.086626] CPU: 1 PID: 93 Comm: grep Not tainted 3.14.0-rc4 #39 [ 246.086992] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 246.087420] [] (show_stack) from [] (dump_stack+0x84/0x94) [ 246.087825] [] (dump_stack) from [] (watchdog_timer_fn+0x144/0x17c) [ 246.088260] [] (watchdog_timer_fn) from [] (__run_hrtimer.isra.32+0x54/0xe4) [ 246.088726] [] (__run_hrtimer.isra.32) from [] (hrtimer_interrupt+0x11c/0x2d0) [ 246.089190] [] (hrtimer_interrupt) from [] (arch_timer_handler_virt+0x28/0x30) [ 246.089670] [] (arch_timer_handler_virt) from [] (handle_percpu_devid_irq+0x6c/0x84) [ 246.090155] [] (handle_percpu_devid_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 246.090822] [] (generic_handle_irq) from [] (handle_IRQ+0x40/0x90) [ 246.091233] [] (handle_IRQ) from [] (gic_handle_irq+0x2c/0x5c) [ 246.091631] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) [ 246.092007] Exception stack(0xc09e7eb0 to 0xc09e7ef8) [ 246.092291] 7ea0: edfe0840 00000001 2d201000 c005048c [ 246.092719] 7ec0: 00000001 c0de209c 00000100 edfe0840 c0ddf840 c0ddf840 00000007 40000005 [ 246.093142] 7ee0: c0dde340 c09e7ef8 c00504c0 c0050208 20000113 ffffffff [ 246.093647] [] (__irq_svc) from [] (rebalance_domains+0x0/0x284) [ 246.094422] [] (rebalance_domains) from [] (0xc09e6028) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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