rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5885/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=17513, q=115031 ncpus=2)
task:kworker/0:6     state:R  running task     stack:22968 pid:5885  tgid:5885  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:seqcount_lockdep_reader_access+0x17e/0x1c0 include/linux/seqlock.h:75
Code: f8 4d 85 e4 75 16 e8 11 ad 3e f8 eb 15 e8 0a ad 3e f8 e8 35 f5 cd 01 4d 85 e4 74 ea e8 fb ac 3e f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0018:ffffc90004bdf900 EFLAGS: 00000293
RAX: ffffffff89812265 RBX: 0000000000000000 RCX: ffff88806cdbbc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004bdf9b0 R08: ffffffff8f7daf77 R09: 1ffffffff1efb5ee
R10: dffffc0000000000 R11: fffffbfff1efb5ef R12: 0000000000000200
R13: ffff888031682c18 R14: 1ffff9200097bf20 R15: dffffc0000000000
 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline]
 gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1534
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>