------------[ cut here ]------------
WARNING: CPU: 1 PID: 97 at kernel/locking/lockdep.c:4817 remove_class_from_lock_chain kernel/locking/lockdep.c:4797 [inline]
WARNING: CPU: 1 PID: 97 at kernel/locking/lockdep.c:4817 remove_class_from_lock_chains kernel/locking/lockdep.c:4837 [inline]
WARNING: CPU: 1 PID: 97 at kernel/locking/lockdep.c:4817 zap_class+0x76b/0xe60 kernel/locking/lockdep.c:4877
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 97 Comm: kworker/u4:2 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x3e kernel/panic.c:582
 report_bug+0x289/0x300 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:remove_class_from_lock_chain kernel/locking/lockdep.c:4817 [inline]
RIP: 0010:remove_class_from_lock_chains kernel/locking/lockdep.c:4837 [inline]
RIP: 0010:zap_class+0x76b/0xe60 kernel/locking/lockdep.c:4877
Code: c1 e8 03 42 0f b6 14 30 4c 89 e0 83 e0 07 83 c0 01 38 d0 7c 80 84 d2 0f 84 78 ff ff ff 4c 89 e7 e8 6a 82 58 00 e9 6b ff ff ff <0f> 0b e8 7e 8a 31 02 e9 4e fb ff ff 48 89 4d a8 48 89 55 c0 e8 8c
RSP: 0018:ffffc900011c78e8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8ada5280 RCX: 00000000000005f9
RDX: 0000000000000000 RSI: ffffffff838d5c7a RDI: 0000000000000006
RBP: ffffc900011c7950 R08: ffff8880a902c540 R09: fffffbfff1658997
R10: fffffbfff1658996 R11: ffffffff8b2c4cb7 R12: ffffffff8b27bc08
R13: ffffffff8ae506a8 R14: dffffc0000000000 R15: ffffffff8ae506a0
 __lockdep_free_key_range+0x64/0x120 kernel/locking/lockdep.c:5000
 lockdep_unregister_key+0x201/0x4c0 kernel/locking/lockdep.c:5192
 netdev_unregister_lockdep_key net/core/dev.c:9172 [inline]
 free_netdev+0x2df/0x470 net/core/dev.c:9835
 netdev_run_todo+0x64a/0x7d0 net/core/dev.c:9580
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112
 ip_tunnel_delete_nets+0x42a/0x600 net/ipv4/ip_tunnel.c:1114
 erspan_exit_batch_net+0x23/0x30 net/ipv4/ip_gre.c:1600
 ops_exit_list.isra.0+0x10c/0x160 net/core/net_namespace.c:175
 cleanup_net+0x538/0xaf0 net/core/net_namespace.c:597
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..