rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3857/1:b..l P4374/1:b..l
	(detected by 0, t=10502 jiffies, g=55781, q=215 ncpus=2)
task:kworker/u4:13   state:R  running task     stack:19608 pid:4374  ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x30 kernel/rcu/update.c:279
Code: ad 97 f4 03 00 75 e7 48 c7 c7 00 01 0c 8b 48 c7 c6 20 25 0c 8b e8 70 20 ad f6 0f 0b eb d0 cc cc cc cc cc cc cc cc cc cc cc cc <31> c0 83 3d e7 63 f4 03 00 74 1d 83 3d 72 97 f4 03 00 74 14 65 48
RSP: 0018:ffffc90016e47a38 EFLAGS: 00000292
RAX: 85dd3d81348e2200 RBX: 000000000001de68 RCX: 1ffff92002dc8ec8
RDX: dffffc0000000000 RSI: ffffffff8b0c13e0 RDI: ffffffff8b5d62c0
RBP: ffffc90016e47b70 R08: dffffc0000000000 R09: fffffbfff20e7645
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92002dc8f62
R13: dffffc0000000000 R14: ffff88814b8ef340 R15: ffffffff9238bae0
 rcu_read_lock include/linux/rcupdate.h:792 [inline]
 inet_twsk_purge+0x159/0xa40 net/ipv4/inet_timewait_sock.c:295
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:604
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
task:kworker/u4:8    state:R  running task     stack:20736 pid:3857  ppid:2      flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6727
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 unwind_next_frame+0x1a55/0x2220 arch/x86/kernel/unwind_orc.c:629
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:692 [inline]
 sctp_inet6addr_event+0x363/0x700 net/sctp/ipv6.c:86
 notifier_call_chain kernel/notifier.c:87 [inline]
 atomic_notifier_call_chain+0x17c/0x2c0 kernel/notifier.c:225
 ipv6_add_addr+0xc31/0xee0 net/ipv6/addrconf.c:1181
 addrconf_add_linklocal+0x344/0xae0 net/ipv6/addrconf.c:3242
 addrconf_addr_gen+0x856/0xbe0
 addrconf_dev_config net/ipv6/addrconf.c:3418 [inline]
 addrconf_init_auto_addrs+0x945/0xe60 net/ipv6/addrconf.c:3496
 addrconf_notify+0xade/0xf60 net/ipv6/addrconf.c:3669
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455
 call_netdevice_notifiers_info net/core/dev.c:1970 [inline]
 netdev_state_change+0x1a3/0x250 net/core/dev.c:1359
 linkwatch_do_dev+0x10c/0x160 net/core/link_watch.c:168
 __linkwatch_run_queue+0x448/0x6b0 net/core/link_watch.c:221
 linkwatch_event+0x48/0x50 net/core/link_watch.c:264
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 9991 jiffies! g55781 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:25368 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567