INFO: task :8924 can't die for more than 143 seconds. R running task 29432 8924 8876 0x00004006 Call Trace: context_switch kernel/sched/core.c:3388 [inline] __schedule+0x8e9/0x1f30 kernel/sched/core.c:4081 Showing all locks held in the system: 1 lock held by khungtaskd/1078: #0: ffffffff88fac6c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5336 1 lock held by rsyslogd/8749: #0: ffff8880a0df4620 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8839: #0: ffff888094b0a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f432e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8840: #0: ffff8880a3c67090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8841: #0: ffff88809951b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f532e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8842: #0: ffff8880a731e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f4b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8843: #0: ffff8880a7740090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f4f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8844: #0: ffff88809025a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8845: #0: ffff88809a44b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1078 Comm: khungtaskd Not tainted 5.4.0-rc7-next-20191113 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:269 [inline] watchdog+0xc8f/0x1350 kernel/hung_task.c:353 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8924 Comm: Not tainted 5.4.0-rc7-next-20191113 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x2b/0x50 kernel/kcov.c:190 Code: 48 89 e5 65 48 8b 04 25 80 fe 01 00 65 8b 15 64 52 8e 7e 81 e2 00 01 1f 00 48 8b 75 08 75 2b 8b 90 00 13 00 00 83 fa 02 75 20 <48> 8b 88 08 13 00 00 8b 80 04 13 00 00 48 8b 11 48 83 c2 01 48 39 RSP: 0018:ffff88805b72fbf8 EFLAGS: 00000246 RAX: ffff888091e8a180 RBX: 0000000000000002 RCX: ffffffff817e1f96 RDX: 0000000000000002 RSI: ffffffff817e1f61 RDI: 0000000000000005 RBP: ffff88805b72fbf8 R08: ffff888091e8a180 R09: ffffed1014144c81 R10: ffffed1014144c80 R11: ffff8880a0a26403 R12: ffff8880a0a26400 R13: 0000000000000003 R14: ffffed1014144c80 R15: ffff88805b72fcc8 FS: 00007f3b50e91700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0d635ab000 CR3: 0000000096f80000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rep_nop arch/x86/include/asm/processor.h:650 [inline] cpu_relax arch/x86/include/asm/processor.h:655 [inline] irq_work_sync+0xd1/0x1d0 kernel/irq_work.c:194 _free_event+0x89/0x13b0 kernel/events/core.c:4569 put_event+0x47/0x60 kernel/events/core.c:4694 perf_event_release_kernel+0x6d5/0xd70 kernel/events/core.c:4809 perf_release+0x37/0x50 kernel/events/core.c:4819 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3b50e90c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: 0000000020ffb000 RBX: 0000000000000006 RCX: 000000000045a219 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffb000 RBP: 000000000075c070 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007f3b50e916d4 R13: 00000000004c6c31 R14: 00000000004dc3b8 R15: 00000000ffffffff