rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P19309/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=207505, q=739972 ncpus=2)
task:kworker/1:3     state:R  running task     stack:21656 pid:19309 tgid:19309 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7189
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
 irqentry_exit+0x1fe/0x790 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 9b 6e 26 12 83 f8 01 0f 85 28 01 00 00 9c 58 f6 c4 02 0f 85 13 01 00 00 41 f7 c6 00 02 00 00 0f 85 c0 00 00 00 <48> 8b 44 24 10 65 48 2b 05 ed 26 26 12 0f 85 4e 01 00 00 48 83 c4
RSP: 0018:ffffc9000384faf8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e7e54e0 RCX: ffffc9000384fb04
RDX: 0000000000000002 RSI: ffffffff8defa963 RDI: ffffffff8c1c3600
RBP: ffffffff89af0fc9 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880538d4a00
R13: 0000000000040000 R14: 0000000000000202 R15: 0000000000000003
 rcu_lock_release include/linux/rcupdate.h:310 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 gc_worker+0x94e/0x1630 net/netfilter/nf_conntrack_core.c:1614
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>