INFO: task :22351 can't die for more than 143 seconds. R running task 28560 22351 8901 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: 3 locks held by kworker/u4:4/263: #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880a994ad28 ((wq_completion)netns){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffff8880a91efdc0 (net_cleanup_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff899ad348 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0xaf0 net/core/net_namespace.c:559 1 lock held by khungtaskd/1081: #0: ffffffff88fac6c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5336 1 lock held by rsyslogd/8770: #0: ffff8880a4d071a0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8860: #0: ffff88809c95e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f472e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8861: #0: ffff8880941b4090 (&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/8862: #0: ffff8880a8bf8090 (&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/8863: #0: ffff88809873e090 (&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/8864: #0: ffff88808c141090 (&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/8865: #0: ffff88809c2c5090 (&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/8866: #0: ffff88809a4ab090 (&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: 1081 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: 318 Comm: kworker/u4:5 Not tainted 5.4.0-rc7-next-20191113 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_tt_purge RIP: 0010:mark_lock+0x116/0x1220 kernel/locking/lockdep.c:3644 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 22 0e 00 00 41 be 01 00 00 00 44 89 e1 41 d3 e6 4d 63 f6 4c 85 73 50 0f 84 2f 01 00 00 <41> bf 01 00 00 00 e9 3a ff ff ff e8 fa 18 eb 01 85 c0 0f 84 2a ff RSP: 0018:ffff8880a8e17af8 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: ffffffff8a7f2410 RCX: 0000000000000002 RDX: 1ffffffff14fe48c RSI: 0000000000000008 RDI: ffffffff8a7f2460 RBP: ffff8880a8e17b48 R08: 1ffffffff14f4351 R09: fffffbfff14f4352 R10: fffffbfff14f4351 R11: ffffffff8a7a1a8f R12: 0000000000000002 R13: ffff8880a8e08c88 R14: 0000000000000004 R15: ffff8880a8e08c60 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000039316000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_held_locks+0xa4/0xf0 kernel/locking/lockdep.c:3360 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3381 [inline] lockdep_hardirqs_on+0x19e/0x5e0 kernel/locking/lockdep.c:3434 trace_hardirqs_on+0x67/0x240 kernel/trace/trace_preemptirq.c:31 __local_bh_enable_ip+0x15a/0x270 kernel/softirq.c:194 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x2c/0x30 kernel/locking/spinlock.c:207 spin_unlock_bh include/linux/spinlock.h:383 [inline] batadv_tt_local_purge+0x27a/0x360 net/batman-adv/translation-table.c:1446 batadv_tt_purge+0x2e/0xa30 net/batman-adv/translation-table.c:3801 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352