syzbot

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Looking for class "&sdp->delay_work)" with key __key.4, but found a different class "(&sdp->delay_work)" with the same key
WARNING: CPU: 0 PID: 1088 at kernel/locking/lockdep.c:932 look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Modules linked in:
CPU: 0 PID: 1088 Comm: kworker/u32:6 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Code: c7 c7 a0 b7 2c 8b e8 ec a3 74 f6 90 0f 0b 90 90 90 31 db eb be c6 05 74 d6 ef 04 01 90 48 c7 c7 c0 ba 2c 8b e8 ce a3 74 f6 90 <0f> 0b 90 90 e9 62 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000007938 EFLAGS: 00010086
RAX: 0000000000000000 RBX: ffffffff94265960 RCX: ffffffff81510229
RDX: ffff8880190ca440 RSI: ffffffff81510236 RDI: 0000000000000001
RBP: ffffffff94ad6ac0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 20676e696b6f6f4c R12: ffffc90000007cc0
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff94ad5be0
FS:  0000000000000000(0000) GS:ffff88802c000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f73f9e9c CR3: 000000000d97a000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 register_lock_class+0xb1/0x1230 kernel/locking/lockdep.c:1284
 __lock_acquire+0x111/0x3b30 kernel/locking/lockdep.c:5014
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 call_timer_fn+0x120/0x610 kernel/time/timer.c:1789
 expire_timers kernel/time/timer.c:1843 [inline]
 __run_timers+0x74b/0xaf0 kernel/time/timer.c:2417
 __run_timer_base kernel/time/timer.c:2428 [inline]
 __run_timer_base kernel/time/timer.c:2421 [inline]
 run_timer_base+0x111/0x190 kernel/time/timer.c:2437
 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2447
 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554
 do_softirq kernel/softirq.c:455 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:442
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 __fib6_clean_all+0x108/0x2d0 net/ipv6/ip6_fib.c:2273
 rt6_sync_down_dev net/ipv6/route.c:4906 [inline]
 rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911
 addrconf_ifdown.isra.0+0x117/0x1a70 net/ipv6/addrconf.c:3855
 addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992
 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
 call_netdevice_notifiers net/core/dev.c:2044 [inline]
 dev_close_many+0x333/0x6a0 net/core/dev.c:1585
 unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193
 unregister_netdevice_many net/core/dev.c:11276 [inline]
 default_device_exit_batch+0x731/0x9b0 net/core/dev.c:11759
 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178
 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>