perf_callchain() hang

Found by

perf_fuzzer

Severity

Lockup/Hang

First Seen

3.19.0+

Most recently Seen

4.0-rc1

Reproducible

Yes (but you might have to run the test case a few times to trigger)

Found On

Haswell

Linux-kernel

19 February 2015 -- perf: fuzzer gets CPU stuck in perf_callchain()

Introduced by

Fixed in

4.0 -- d525211f9d1be8b523ec7633f080f2116f5ea536

Kernel Splat

  1. *** perf_fuzzer 0.30-pre *** by Vince Weaver
    
            Linux version 3.19.0+ x86_64
            Processor: Intel 6/60/3
    
            Seeding random number generator with 1424717287
            /proc/sys/kernel/perf_event_max_sample_rate currently: 6250/s
            /proc/sys/kernel/perf_event_paranoid currently: 1
            Logging perf_event_open() failures: no
            Running fsync after every syscall: no
            To reproduce, try: ./perf_fuzzer -s 30000 -r 1424717287
    
    Pid=9176, sleeping 1s
    ==================================================
    Fuzzing the following syscalls:
            mmap perf_event_open close read write ioctl fork prctl poll 
    *NOT* Fuzzing the following syscalls:
            
    Also attempting the following:
            signal-handler-on-overflow busy-instruction-loop accessing-perf-proc-and-sys-files trashing-the-mmap-page 
    *NOT* attempting the following:
    ==================================================
    Iteration 10000
            Open attempts: 207133  Successful: 938
                    EPERM : 42
                    ENOENT : 1678
                    E2BIG : 19953
                    EBADF : 9476
                    EACCES : 1034
                    EINVAL : 173426
                    ENOSPC : 6
                    EOPNOTSUPP : 580
                    Type (Hardware 233/27305)(software 322/30705)(tracepoint 83/30510)(Cache 80/25604)(cpu 190/30144)(breakpoint 30/30569)(power 0/4400)(uncore_imc 0/4227)(#8 0/101)(#9 0/35)(#10 0/49)(#11 0/24)(#12 0/31)(#13 0/22)(#14 0/30)(>14 0/23377)
            Close attempts: 905  Successful: 905
            Read attempts: 884  Successful: 790
            Write attempts: 915  Successful: 0
            Ioctl attempts: 837  Successful: 371
            Mmap attempts: 938  Successful: 378
            Prctl attempts: 907  Successful: 907
            Fork attempts: 450  Successful: 450
            Poll attempts: 918  Successful: 893
            Access attempts: 956  Successful: 465
            Trash mmap attempts: 916  Successful: 916
            Overflows: 0
            SIGIOs due to RT signal queue full: 0
    [335638.252654] ------------[ cut here ]------------
    [335638.257675] WARNING: CPU: 1 PID: 9176 at kernel/watchdog.c:290 watchdog_overflow_callback+0x92/0xc0()
    [335638.267649] Watchdog detected hard LOCKUP on cpu 1
    [335638.272715] Modules linked in: fuse x86_pkg_temp_thermal snd_hda_codec_realtek snd_hda_codec_hdmi snd_hda_codec_generic intel_powerclamp intel_rapl iosf_mbi coretemp snd_hda_intel kvm snd_hda_controller crct10dif_pclmul snd_hda_codec crc32_pclmul snd_hwdep ghash_clmulni_intel snd_pcm aesni_intel i915 snd_timer ppdev aes_x86_64 evdev drm_kms_helper iTCO_wdt lrw snd drm mei_me gf128mul iTCO_vendor_support soundcore glue_helper mei parport_pc xhci_pci i2c_algo_bit tpm_tis tpm ablk_helper i2c_i801 cryptd lpc_ich mfd_core battery video xhci_hcd parport processor wmi psmouse pcspkr serio_raw button sg sr_mod cdrom sd_mod ahci ehci_pci libahci ehci_hcd libata e1000e scsi_mod ptp crc32c_intel usbcore usb_common pps_core thermal fan thermal_sys
    [335638.344480] CPU: 1 PID: 9176 Comm: perf_fuzzer Not tainted 3.19.0+ #128
    [335638.351642] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014
    [335638.359638]  ffffffff81a49b7f ffff88011ea45aa0 ffffffff816c2a19 0000000000000000
    [335638.367755]  ffff88011ea45af0 ffff88011ea45ae0 ffffffff8106deaa ffff88011ea45b00
    [335638.375871]  ffff880119b8f800 0000000000000000 ffff88011ea45c40 ffff88011ea45ef8
    [335638.383969] Call Trace:
    [335638.386688]    [] dump_stack+0x45/0x57
    [335638.392997]  [] warn_slowpath_common+0x8a/0xc0
    [335638.399554]  [] warn_slowpath_fmt+0x46/0x50
    [335638.405807]  [] ? native_sched_clock+0x2a/0x90
    [335638.412333]  [] ? native_sched_clock+0x2a/0x90
    [335638.418865]  [] watchdog_overflow_callback+0x92/0xc0
    [335638.425946]  [] __perf_event_overflow+0x91/0x270
    [335638.432641]  [] ? x86_perf_event_set_period+0xca/0x170
    [335638.439932]  [] perf_event_overflow+0x19/0x20
    [335638.446393]  [] intel_pmu_handle_irq+0x1ba/0x3a0
    [335638.453110]  [] perf_event_nmi_handler+0x2b/0x50
    [335638.460433]  [] nmi_handle+0xa0/0x150
    [335638.466715]  [] ? nmi_handle+0x5/0x150
    [335638.473094]  [] default_do_nmi+0x4a/0x140
    [335638.479780]  [] do_nmi+0x98/0xe0
    [335638.485576]  [] end_repeat_nmi+0x1e/0x2e
    [335638.492132]  [] ? trace_page_fault+0x30/0x30
    [335638.499083]  [] ? trace_page_fault+0x30/0x30
    [335638.506012]  [] ? trace_page_fault+0x30/0x30
    [335638.512900]  <>    [] ? copy_user_handle_tail+0x3b/0x80
    [335638.521843]  [] copy_from_user_nmi+0x63/0x70
    [335638.528815]  [] perf_callchain_user+0xd0/0x240
    [335638.535934]  [] ? __perf_event_overflow+0xd9/0x270
    [335638.543427]  [] perf_callchain+0x1f8/0x220
    [335638.550187]  [] perf_prepare_sample+0x291/0x3c0
    [335638.557404]  [] ? perf_swevent_event+0x67/0x90
    [335638.564556]  [] __perf_event_overflow+0x10e/0x270
    [335638.571961]  [] ? __perf_event_overflow+0xd9/0x270
    [335638.579486]  [] perf_swevent_overflow+0xa9/0xe0
    [335638.586786]  [] perf_swevent_event+0x67/0x90
    [335638.593746]  [] perf_tp_event+0xc4/0x210
    [335638.600335]  [] ? lock_release+0x130/0x260
    [335638.607138]  [] ? __lock_acquire.isra.31+0x3af/0xfe0
    [335638.614822]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [335638.622332]  [] ? perf_trace_lock+0x12a/0x160
    [335638.629377]  [] ? __sigqueue_alloc+0x5/0x150
    [335638.636312]  [] ? __sigqueue_alloc+0x134/0x150
    [335638.643429]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [335638.650947]  [] ? __lock_task_sighand+0x6e/0x110
    [335638.658293]  [] perf_trace_lock+0x12a/0x160
    [335638.665163]  [] ? __lock_task_sighand+0x78/0x110
    [335638.672481]  [] ? do_send_sig_info+0x5d/0x80
    [335638.679409]  [] lock_release+0x130/0x260
    [335638.685968]  [] _raw_spin_unlock_irqrestore+0x24/0x40
    [335638.693716]  [] do_send_sig_info+0x5d/0x80
    [335638.700483]  [] send_sigio_to_task+0x12f/0x1a0
    [335638.707592]  [] ? send_sigio_to_task+0x5/0x1a0
    [335638.714768]  [] ? send_sigio+0x56/0x100
    [335638.721256]  [] send_sigio+0xae/0x100
    [335638.727556]  [] kill_fasync+0x97/0xf0
    [335638.733868]  [] ? kill_fasync+0xf/0xf0
    [335638.740274]  [] perf_event_wakeup+0xd4/0xf0
    [335638.747103]  [] ? perf_event_wakeup+0x5/0xf0
    [335638.754045]  [] ? __do_softirq+0x22f/0x290
    [335638.760779]  [] perf_pending_event+0x33/0x60
    [335638.767680]  [] irq_work_run_list+0x4c/0x80
    [335638.774481]  [] irq_work_run+0x18/0x40
    [335638.780814]  [] smp_irq_work_interrupt+0x2e/0x40
    [335638.788052]  [] irq_work_interrupt+0x6d/0x80
    [335638.794947]    [] ? _raw_spin_unlock+0x2b/0x40
    [335638.802442]  [] ? generic_exec_single+0x133/0x190
    [335638.809701]  [] ? task_clock_event_add+0x40/0x40
    [335638.816839]  [] smp_call_function_single+0x67/0xa0
    [335638.824178]  [] task_function_call+0x49/0x60
    [335638.830977]  [] ? perf_event_sched_in+0xa0/0xa0
    [335638.838029]  [] _perf_event_enable+0x90/0xf0
    [335638.844816]  [] ? task_function_call+0x60/0x60
    [335638.851784]  [] perf_event_for_each_child+0x3f/0xb0
    [335638.859234]  [] perf_event_task_enable+0x7c/0xd0
    [335638.866359]  [] SyS_prctl+0x26d/0x4d0
    [335638.872478]  [] system_call_fastpath+0x16/0x1b
    [335638.879446] ---[ end trace 4ad3a65969f2b314 ]---
    [335638.885003] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 632.284 msecs
    [335638.894402] perf interrupt took too long (4940903 > 38461), lowering kernel.perf_event_max_sample_rate to 3250
    [335647.623863] perf interrupt took too long (4902309 > 71428), lowering kernel.perf_event_max_sample_rate to 1750
    [335650.095436] INFO: rcu_sched detected stalls on CPUs/tasks: { 1} (detected by 5, t=5252 jiffies, g=24160777, c=24160776, q=240)
    
  2. Stopping after 30000
    Watchdog enabled with timeout 60s
    Will auto-exit if signal storm detected
    
    *** perf_fuzzer 0.30-pre *** by Vince Weaver
    
            Linux version 3.19.0+ x86_64
            Processor: Intel 6/60/3
    
            Seeding random number generator with 1424327180
            /proc/sys/kernel/perf_event_max_sample_rate currently: 50000/s
            /proc/sys/kernel/perf_event_paranoid currently: 1
            Logging perf_event_open() failures: no
            Running fsync after every syscall: no
            To reproduce, try: ./perf_fuzzer -s 30000 -r 1424327180
    
    Pid=3921, sleeping 1s
    ==================================================
    Fuzzing the following syscalls:
            mmap perf_event_open close read write ioctl fork prctl poll 
    *NOT* Fuzzing the following syscalls:
            
    Also attempting the following:
            signal-handler-on-overflow busy-instruction-loop accessing-perf-proc-and-sys-files trashing-the-mmap-page 
    *NOT* attempting the following:
            
    ==================================================
    Iteration 10000
            Open attempts: 195229  Successful: 920
                    EPERM : 27
                    ENOENT : 1640
                    E2BIG : 18829
                    EBADF : 9066
                    EACCES : 956
                    EINVAL : 163244
                    EOPNOTSUPP : 547
                    Type (Hardware 213/25831)(software 360/29001)(tracepoint 80/28845)(Cache 78/24213)(cpu 170/28287)(breakpoint 19/28643)(power 0/3991)(uncore_imc 0/4028)(#8 0/78)(#9 0/31)(#10 0/24)(#11 0/24)(#12 0/24)(#13 0/24)(#14 0/23)(>14 0/22162)
    
            Close attempts: 877  Successful: 877
            Read attempts: 861  Successful: 792
            Write attempts: 897  Successful: 0
            Ioctl attempts: 937  Successful: 395
            Mmap attempts: 920  Successful: 374
            Prctl attempts: 892  Successful: 892
            Fork attempts: 463  Successful: 463
            Poll attempts: 916  Successful: 874
            Access attempts: 904  Successful: 438
            Trash mmap attempts: 919  Successful: 919
            Overflows: 0
            SIGIOs due to RT signal queue full: 0
    [ 7938.495396] ------------[ cut here ]------------
    [ 7938.500373] WARNING: CPU: 2 PID: 5692 at kernel/watchdog.c:290 watchdog_overflow_callback+0x92/0xc0()
    [ 7938.510337] Watchdog detected hard LOCKUP on cpu 2
    [ 7938.515301] Modules linked in: fuse x86_pkg_temp_thermal intel_powerclamp intel_rapl iosf_mbi coretemp kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel snd_hda_controller snd_hda_codec i915 aes_x86_64 lrw gf128mul ppdev iTCO_wdt xhci_pci snd_hwdep snd_pcm tpm_tis evdev glue_helper iTCO_vendor_support xhci_hcd snd_timer mei_me drm_kms_helper ablk_helper snd tpm mei drm psmouse serio_raw pcspkr parport_pc cryptd soundcore lpc_ich parport wmi mfd_core battery i2c_i801 i2c_algo_bit button processor video sg sr_mod sd_mod cdrom ahci libahci ehci_pci libata ehci_hcd e1000e ptp crc32c_intel scsi_mod usbcore usb_common pps_core fan thermal thermal_sys
    [ 7938.586970] CPU: 2 PID: 5692 Comm: perf_fuzzer Not tainted 3.19.0+ #127
    [ 7938.594053] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014
    [ 7938.601990]  ffffffff81a41afe ffff88011ea85aa0 ffffffff816bfed5 0000000000000000
    [ 7938.610056]  ffff88011ea85af0 ffff88011ea85ae0 ffffffff8106ddfa 0000000000000000
    [ 7938.618102]  ffff8801195a1800 0000000000000000 ffff88011ea85c40 ffff88011ea85ef8
    [ 7938.626105] Call Trace:
    [ 7938.628735]    [] dump_stack+0x45/0x57
    [ 7938.634940]  [] warn_slowpath_common+0x8a/0xc0
    [ 7938.641394]  [] warn_slowpath_fmt+0x46/0x50
    [ 7938.647566]  [] watchdog_overflow_callback+0x92/0xc0
    [ 7938.654617]  [] __perf_event_overflow+0x91/0x270
    [ 7938.661233]  [] ? x86_perf_event_set_period+0xca/0x170
    [ 7938.668419]  [] perf_event_overflow+0x19/0x20
    [ 7938.674764]  [] intel_pmu_handle_irq+0x1ba/0x3a0
    [ 7938.681432]  [] perf_event_nmi_handler+0x2b/0x50
    [ 7938.688055]  [] nmi_handle+0xa0/0x150
    [ 7938.693681]  [] ? nmi_handle+0x5/0x150
    [ 7938.699405]  [] default_do_nmi+0x4a/0x140
    [ 7938.705429]  [] do_nmi+0x98/0xe0
    [ 7938.710573]  [] end_repeat_nmi+0x1e/0x2e
    [ 7938.716470]  [] ? copy_from_user_nmi+0x20/0x70
    [ 7938.722929]  [] ? copy_from_user_nmi+0x20/0x70
    [ 7938.729386]  [] ? copy_from_user_nmi+0x20/0x70
    [ 7938.735862]  <>    [] ? perf_callchain_user+0xd0/0x240
    [ 7938.744067]  [] perf_callchain+0x1f8/0x220
    [ 7938.750152]  [] perf_prepare_sample+0x291/0x3c0
    [ 7938.756700]  [] __perf_event_overflow+0x10e/0x270
    [ 7938.763412]  [] ? __perf_event_overflow+0xd9/0x270
    [ 7938.770254]  [] ? perf_tp_event+0xc4/0x210
    [ 7938.776302]  [] ? perf_prepare_sample+0x2ec/0x3c0
    [ 7938.783021]  [] ? trace_page_fault+0x28/0x30
    [ 7938.789319]  [] perf_swevent_overflow+0xa9/0xe0
    [ 7938.795845]  [] perf_swevent_event+0x67/0x90
    [ 7938.802139]  [] perf_tp_event+0xc4/0x210
    [ 7938.808025]  [] ? lock_release+0x130/0x260
    [ 7938.814132]  [] ? __lock_acquire.isra.31+0x3af/0xfe0
    [ 7938.821124]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [ 7938.827926]  [] ? perf_trace_lock+0x12a/0x160
    [ 7938.834291]  [] ? __sigqueue_alloc+0x5/0x150
    [ 7938.840541]  [] ? __sigqueue_alloc+0x134/0x150
    [ 7938.847009]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [ 7938.853835]  [] ? __lock_task_sighand+0x6e/0x110
    [ 7938.861174]  [] perf_trace_lock+0x12a/0x160
    [ 7938.867972]  [] ? __lock_task_sighand+0x78/0x110
    [ 7938.875256]  [] ? do_send_sig_info+0x5d/0x80
    [ 7938.882197]  [] lock_release+0x130/0x260
    [ 7938.888754]  [] _raw_spin_unlock_irqrestore+0x24/0x40
    [ 7938.896510]  [] do_send_sig_info+0x5d/0x80
    [ 7938.903240]  [] send_sigio_to_task+0x12f/0x1a0
    [ 7938.910365]  [] ? send_sigio_to_task+0x5/0x1a0
    [ 7938.917455]  [] ? send_sigio+0x56/0x100
    [ 7938.923894]  [] send_sigio+0xae/0x100
    [ 7938.930132]  [] kill_fasync+0x97/0xf0
    [ 7938.936359]  [] ? kill_fasync+0xf/0xf0
    [ 7938.942707]  [] perf_event_wakeup+0xd4/0xf0
    [ 7938.949522]  [] ? perf_event_wakeup+0x5/0xf0
    [ 7938.956367]  [] perf_pending_event+0x33/0x60
    [ 7938.963199]  [] irq_work_run_list+0x4c/0x80
    [ 7938.969932]  [] irq_work_run+0x18/0x40
    [ 7938.976212]  [] smp_trace_irq_work_interrupt+0x3f/0xc0
    [ 7938.983957]  [] trace_irq_work_interrupt+0x6d/0x80
    [ 7938.991362]    [] ? _raw_spin_unlock+0x2b/0x40
    [ 7938.998883]  [] ? generic_exec_single+0x133/0x190
    [ 7939.006127]  [] ? task_clock_event_add+0x40/0x40
    [ 7939.013297]  [] smp_call_function_single+0x67/0xa0
    [ 7939.020568]  [] task_function_call+0x49/0x60
    [ 7939.027277]  [] ? perf_event_sched_in+0xa0/0xa0
    [ 7939.034270]  [] _perf_event_enable+0x90/0xf0
    [ 7939.040963]  [] ? task_function_call+0x60/0x60
    [ 7939.047863]  [] perf_event_for_each_child+0x3f/0xb0
    [ 7939.055259]  [] perf_event_task_enable+0x7c/0xd0
    [ 7939.062321]  [] SyS_prctl+0x26d/0x4d0
    [ 7939.068359]  [] system_call_fastpath+0x16/0x1b
    [ 7939.075261] ---[ end trace 8e72f55d0f5cbae4 ]---
    [ 7939.080732] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 585.271 msecs
    [ 7939.090016] perf interrupt took too long (4572449 > 5000), lowering kernel.perf_event_max_sample_rate to 25000
    [ 7940.065563] INFO: rcu_sched detected stalls on CPUs/tasks: { 2} (detected by 3, t=5252 jiffies, g=10488, c=10487, q=196)
    [ 7940.077820] Task dump for CPU 2:
    [ 7940.081779] perf_fuzzer     R  running task        0  5692   2549 0x0000000c
    [ 7940.089901]  00007ffff86e99b8 000000000000002b 0000000000000003 ffff8800a4103cd8
    [ 7940.098442]  ffffffff810b643f ffff88011897a4d0 0000000000000003 ffff88011897a4d0
    [ 7940.106955]  ffff8800ced65020 ffff8800a4103c98 ffffffff810b52b8 ffff8800a4103cb8
    [ 7940.115473] Call Trace:
    [ 7940.118593]  [] ? __lock_acquire.isra.31+0x3af/0xfe0
    [ 7940.126120]  [] ? __lock_is_held+0x58/0x80
    [ 7940.132660]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [ 7940.139989]  [] ? perf_trace_lock+0x12a/0x160
    [ 7940.146848]  [] ? __perf_event_enable+0x85/0x2a0
    [ 7940.153971]  [] ? _raw_spin_unlock+0x2b/0x40
    [ 7940.160738]  [] ? generic_exec_single+0x133/0x190
    [ 7940.167964]  [] ? task_clock_event_add+0x40/0x40
    [ 7940.175029]  [] ? smp_call_function_single+0x67/0xa0
    [ 7940.182518]  [] ? task_function_call+0x49/0x60
    [ 7940.189447]  [] ? perf_event_sched_in+0xa0/0xa0
    [ 7940.196485]  [] ? _perf_event_enable+0x90/0xf0
    [ 7940.203430]  [] ? task_function_call+0x60/0x60
    [ 7940.210386]  [] ? perf_event_for_each_child+0x3f/0xb0
    [ 7940.217945]  [] ? perf_event_task_enable+0x7c/0xd0
    [ 7940.225255]  [] ? SyS_prctl+0x26d/0x4d0
    [ 7940.231557]  [] ? system_call_fastpath+0x16/0x1b
    [ 7947.852948] perf interrupt took too long (4536733 > 10000), lowering kernel.perf_event_max_sample_rate to 12500
    [ 7956.620503] perf interrupt took too long (4501296 > 20000), lowering kernel.perf_event_max_sample_rate to 6250
    [ 7965.387462] perf interrupt took too long (4466134 > 38461), lowering kernel.perf_event_max_sample_rate to 3250
    
    
  3. [145965.719358] Call Trace:
    [145965.722845]    [] dump_stack+0x45/0x57
    [145965.729907]  [] warn_slowpath_common+0x8a/0xc0
    [145965.737170]  [] warn_slowpath_fmt+0x46/0x50
    [145965.744103]  [] ? native_sched_clock+0x2a/0x90
    [145965.751356]  [] watchdog_overflow_callback+0x92/0xc0
    [145965.759125]  [] __perf_event_overflow+0x91/0x270
    [145965.766466]  [] ? x86_perf_event_set_period+0xca/0x170
    [145965.774393]  [] perf_event_overflow+0x19/0x20
    [145965.781478]  [] intel_pmu_handle_irq+0x1ba/0x3a0
    [145965.788793]  [] ? trace_page_fault+0x30/0x30
    [145965.795777]  [] perf_event_nmi_handler+0x2b/0x50
    [145965.803049]  [] nmi_handle+0xa0/0x150
    [145965.809335]  [] ? nmi_handle+0x5/0x150
    [145965.815730]  [] default_do_nmi+0xd5/0x140
    [145965.822428]  [] do_nmi+0x98/0xe0
    [145965.828254]  [] end_repeat_nmi+0x1e/0x2e
    [145965.834803]  [] ? general_protection+0x30/0x30
    [145965.841912]  [] ? general_protection+0x30/0x30
    [145965.849073]  [] ? general_protection+0x30/0x30
    [145965.856187]  <>    [] ? copy_user_handle_tail+0x3b/0x80
    [145965.865154]  [] copy_from_user_nmi+0x63/0x70
    [145965.872114]  [] perf_callchain_user+0xd0/0x240
    [145965.879227]  [] perf_callchain+0x1f8/0x220
    [145965.885923]  [] perf_prepare_sample+0x291/0x3c0
    [145965.893151]  [] __perf_event_overflow+0x10e/0x270
    [145965.900562]  [] ? __perf_event_overflow+0xd9/0x270
    [145965.908078]  [] ? lock_release+0x130/0x260
    [145965.914842]  [] perf_swevent_overflow+0xa9/0xe0
    [145965.922072]  [] perf_swevent_event+0x67/0x90
    [145965.929025]  [] perf_tp_event+0xc4/0x210
    [145965.935615]  [] ? lock_release+0x130/0x260
    [145965.942395]  [] ? __lock_task_sighand+0x6e/0x110
    [145965.949648]  [] ? perf_trace_lock+0x12a/0x160
    [145965.956671]  [] ? __lock_task_sighand+0x78/0x110
    [145965.963919]  [] ? do_send_sig_info+0x5d/0x80
    [145965.970858]  [] ? do_send_sig_info+0x5d/0x80
    [145965.977849]  [] ? perf_trace_buf_prepare+0x98/0xf0
    [145965.985330]  [] perf_trace_lock+0x12a/0x160
    [145965.992195]  [] ? send_sigio+0x56/0x100
    [145965.998659]  [] ? send_sigio+0xd0/0x100
    [145966.005169]  [] lock_release+0x130/0x260
    [145966.011716]  [] _raw_read_unlock+0x23/0x40
    [145966.018442]  [] send_sigio+0xd0/0x100
    [145966.024700]  [] kill_fasync+0x97/0xf0
    [145966.030968]  [] ? kill_fasync+0xf/0xf0
    [145966.037365]  [] perf_event_wakeup+0xd4/0xf0
    [145966.044210]  [] ? perf_event_wakeup+0x5/0xf0
    [145966.051060]  [] perf_pending_event+0x33/0x60
    [145966.057950]  [] irq_work_run_list+0x4c/0x80
    [145966.064798]  [] irq_work_run+0x18/0x40
    [145966.071127]  [] smp_trace_irq_work_interrupt+0x3f/0xc0
    [145966.078929]  [] trace_irq_work_interrupt+0x6d/0x80
    [145966.086359]    [] ? _raw_spin_unlock_irq+0x32/0x40
    [145966.094337]  [] ? _raw_spin_unlock_irq+0x2b/0x40
    [145966.101634]  [] finish_task_switch+0x8c/0x140
    [145966.108630]  [] ? finish_task_switch+0x4d/0x140
    [145966.115793]  [] __schedule+0x2d6/0x9f0
    [145966.122115]  [] ? perf_trace_lock+0x29/0x160
    [145966.128909]  [] schedule+0x37/0x90
    [145966.134802]  [] schedule_timeout+0x1bc/0x250
    [145966.141578]  [] ? wait_for_completion+0x28/0x100
    [145966.148660]  [] ? wait_for_completion+0xc4/0x100
    [145966.155795]  [] wait_for_completion+0xcc/0x100
    [145966.162731]  [] ? wake_up_state+0x20/0x20
    [145966.169205]  [] ? call_rcu_bh+0x20/0x20
    [145966.175464]  [] wait_rcu_gp+0x5d/0x80
    [145966.181586]  [] ? ftrace_raw_output_rcu_utilization+0x70/0x70
    [145966.189890]  [] synchronize_sched+0x3a/0x50
    [145966.196573]  [] perf_trace_event_unreg.isra.1+0x3b/0x90
    [145966.204345]  [] perf_trace_destroy+0x3c/0x50
    [145966.211075]  [] tp_perf_event_destroy+0xe/0x10
    [145966.217976]  [] __free_event+0x2c/0x80
    [145966.224102]  [] SYSC_perf_event_open+0x629/0xc80
    [145966.231246]  [] SyS_perf_event_open+0xe/0x10
    [145966.237982]  [] system_call_fastpath+0x16/0x1b
    [145966.244932] ---[ end trace 7088940f25646d60 ]---
    
    

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