rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (1 GPs behind) idle=0a3/1/0x4000000000000002 softirq=85720/85724 fqs=5243 
	(detected by 1, t=10502 jiffies, g=116049, q=1788)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 144 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: netns cleanup_net
RIP: 0010:is_idle_task include/linux/sched.h:1868 [inline]
RIP: 0010:irq_enter_rcu+0x7a/0xe0 kernel/softirq.c:621
Code: c0 75 73 c7 03 00 00 00 00 e8 42 30 73 08 65 48 8b 3d 2a 27 b9 7e 48 8d 5f 2c 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 30 <f6> 03 02 74 1e 65 8b 05 12 27 b9 7e 25 00 ff ff 00 3d 00 00 01 00
RSP: 0018:ffffc900000076e8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888017f8002c RCX: c67f2ec89e796000
RDX: 0000000000000100 RSI: ffffffff8a79f960 RDI: ffff888017f80000
RBP: 0000000000000000 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d
R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe6878fe00 CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x45/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 12 f2 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900000077c0 EFLAGS: 00000206
RAX: c67f2ec89e796000 RBX: 1ffff92000000efc RCX: c67f2ec89e796000
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980
RBP: ffffc900000078a0 R08: ffffffff901d41c7 R09: 1ffffffff203a838
R10: dffffc0000000000 R11: fffffbfff203a839 R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ndisc_send_skb+0xde0/0x1500 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3956
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lockdep_unregister_key+0x4d3/0x520 kernel/locking/lockdep.c:6334
Code: 48 3b 84 24 80 00 00 00 75 39 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 d9 c0 5e 08 41 f7 c4 00 02 00 00 74 90 fb 84 db <75> 8f eb a0 0f 0b e9 44 ff ff ff 0f 0b e9 b0 fe ff ff 0f 0b e9 fd
RSP: 0018:ffffc900016cf7a0 EFLAGS: 00000202
RAX: dffffc0000000000 RBX: ffff888076125101 RCX: c67f2ec89e796000
RDX: 0000000000000001 RSI: ffffffff8a2b3580 RDI: ffffffff8a79f980
RBP: ffffc900016cf880 R08: ffffffff901a5bff R09: 1ffffffff2034b7f
R10: dffffc0000000000 R11: fffffbfff2034b80 R12: 0000000000000a06
R13: ffff888076125129 R14: ffffffff901a4028 R15: 1ffff920002d9ef8
 wq_unregister_lockdep kernel/workqueue.c:3518 [inline]
 destroy_workqueue+0x87b/0xb20 kernel/workqueue.c:4485
 wg_destruct+0x19c/0x300 drivers/net/wireguard/device.c:239
 netdev_run_todo+0x851/0xa70 net/core/dev.c:10717
 default_device_exit_batch+0x369/0x3c0 net/core/dev.c:11694
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x791/0xba0 net/core/net_namespace.c:635
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>