rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6119/3:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=15277, q=11853 ncpus=2)
task:kworker/0:8     state:R  running task     stack:25952 pid:6119  tgid:6119  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: mld mld_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d7/0x3d0 kernel/locking/lockdep.c:5893
Code: 46 7b 11 00 00 00 00 eb b5 e8 45 d3 0d 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 c5 00 7b 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 95 81 6e ff cc 48 8d 3d 72 6d 73
RSP: 0018:ffffc90003c17408 EFLAGS: 00000282
RAX: 4e2e122091c1bb00 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000005 RSI: ffffffff8e16c1b5 RDI: ffffffff8c27d500
RBP: ffff88803151e7a0 R08: ffff88803151db80 R09: 0000000000000002
R10: 00000000fffffff5 R11: 0000000000000000 R12: 0000000000000005
R13: 0000000000000005 R14: ffffffff8e75e5e0 R15: ffff88803151db80
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 fib_rules_lookup+0xc40/0xea0 net/core/fib_rules.c:362
 ip6mr_fib_lookup net/ipv6/ip6mr.c:162 [inline]
 mroute6_is_socket+0x229/0x380 net/ipv6/ip6mr.c:1660
 ip6_finish_output2+0x695/0x13e0 net/ipv6/ip6_output.c:85
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip6_output+0x340/0x550 net/ipv6/ip6_output.c:246
 dst_output include/net/dst.h:470 [inline]
 NF_HOOK+0x177/0x4f0 include/linux/netfilter.h:318
 mld_sendpack+0x8b4/0xe40 net/ipv6/mcast.c:1855
 mld_dad_work+0x45/0x5b0 net/ipv6/mcast.c:2294
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>