rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P25/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=32061, q=818 ncpus=2)
task:kworker/1:0     state:R  running task     stack:25248 pid:25    tgid:25    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7284
 preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7606
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x910 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947
Code: ff ff ff e8 40 2c 43 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 62 27 f2 11 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 7f 30 46 0a cc 48 8d 3d 87 60 da
RSP: 0018:ffffc900001f7940 EFLAGS: 00000292
RAX: 4c0b511fa3f42100 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000dd6da8aa RSI: ffffffff8e69efee RDI: ffffffff8c6dac80
RBP: ffff88801e6f3e80 R08: ffffffff8a0209d4 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff20f4bf0 R12: ffffffff8ed5c920
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 gc_worker+0x298/0x1890 net/netfilter/nf_conntrack_core.c:1532
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>