------------[ cut here ]------------ lockdep bfs error:-1 WARNING: CPU: 1 PID: 202 at kernel/locking/lockdep.c:1960 print_bfs_bug+0x130/0x1e0 kernel/locking/lockdep.c:1960 Modules linked in: CPU: 1 PID: 202 Comm: kworker/u4:4 Not tainted 5.9.0-rc7-next-20200930-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:print_bfs_bug+0x130/0x1e0 kernel/locking/lockdep.c:1960 Code: e2 08 00 74 2c 48 c7 c7 c0 7f a6 8d e8 49 51 01 00 66 90 85 db 75 05 5b 5d 41 5c c3 89 ee 48 c7 c7 20 e8 ab 88 e8 7b e5 c0 06 <0f> 0b 5b 5d 41 5c c3 0f 0b e8 62 82 e9 06 85 c0 74 d7 48 c7 c0 38 RSP: 0018:ffffc90001867318 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: ffff8880a8b62540 RSI: ffffffff815df1a5 RDI: fffff5200030ce55 RBP: 00000000ffffffff R08: 0000000000000001 R09: ffff8880ae520f8b R10: 0000000000000000 R11: 207065646b636f6c R12: ffff8880a8b62540 R13: dffffc0000000000 R14: 0000000000000006 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000746138 CR3: 0000000051c45000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_irq_usage+0x6b4/0xc60 kernel/locking/lockdep.c:2585 check_prev_add kernel/locking/lockdep.c:2823 [inline] check_prevs_add kernel/locking/lockdep.c:2944 [inline] validate_chain kernel/locking/lockdep.c:3562 [inline] __lock_acquire+0x2873/0x56d0 kernel/locking/lockdep.c:4796 lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 alloc_object lib/debugobjects.c:239 [inline] __debug_object_init+0x5c6/0xd10 lib/debugobjects.c:548 debug_object_init lib/debugobjects.c:595 [inline] debug_object_activate+0x32c/0x3e0 lib/debugobjects.c:681 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu kernel/rcu/tree.c:2943 [inline] call_rcu+0x2c/0x7d0 kernel/rcu/tree.c:3030 nf_hook_entries_free net/netfilter/core.c:88 [inline] nf_hook_entries_free net/netfilter/core.c:75 [inline] __nf_unregister_net_hook+0x349/0x500 net/netfilter/core.c:422 nf_unregister_net_hook net/netfilter/core.c:431 [inline] nf_unregister_net_hooks+0x47/0xe0 net/netfilter/core.c:499 nf_ct_netns_do_put+0x253/0x520 net/netfilter/nf_conntrack_proto.c:540 nf_ct_netns_put net/netfilter/nf_conntrack_proto.c:617 [inline] nf_ct_netns_put+0x49/0x80 net/netfilter/nf_conntrack_proto.c:610 nf_conncount_destroy+0x45/0x190 net/netfilter/nf_conncount.c:581 ovs_ct_limit_exit net/openvswitch/conntrack.c:1895 [inline] ovs_ct_exit+0x1f5/0x480 net/openvswitch/conntrack.c:2298 ovs_exit_net+0x1e8/0xba0 net/openvswitch/datapath.c:2532 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:186 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:603 process_one_work+0x933/0x15a0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296