syzbot

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WARNING: CPU: 0 PID: 29467 at kernel/locking/lockdep.c:853 look_up_lock_class kernel/locking/lockdep.c:853 [inline]
WARNING: CPU: 0 PID: 29467 at kernel/locking/lockdep.c:853 register_lock_class+0x1f0/0x1630 kernel/locking/lockdep.c:1201
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 29467 Comm: kworker/u4:1 Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: krdsd rds_shutdown_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 panic+0x382/0x7fb kernel/panic.c:231
 __warn.cold+0x20/0x4b kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:look_up_lock_class kernel/locking/lockdep.c:853 [inline]
RIP: 0010:register_lock_class+0x1f0/0x1630 kernel/locking/lockdep.c:1201
Code: 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 fd 0f 00 00 4d 3b 67 18 74 0b 49 81 3f 00 a5 9a 8c 74 02 <0f> 0b 85 ed 0f 84 b2 00 00 00 f6 44 24 04 01 0f 85 a7 00 00 00 83
RSP: 0018:ffffc90000007a10 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 1ffff92000000f49 RCX: ffffffff8d43e160
RDX: 1ffff92000000fb0 RSI: 0000000000000000 RDI: ffffc90000007d80
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff894e96c0
R13: ffffffff8e002660 R14: ffffffff8d1203e8 R15: ffffc90000007d68
 __lock_acquire+0x101/0x5780 kernel/locking/lockdep.c:4320
 lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029
 call_timer_fn+0x12e/0x760 kernel/time/timer.c:1410
 expire_timers kernel/time/timer.c:1458 [inline]
 __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755
 __run_timers kernel/time/timer.c:1736 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1768
 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x9b/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x235/0x280 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x4d/0x90 kernel/locking/spinlock.c:191
Code: 48 c7 c0 e8 6b fc 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 3c 48 83 3d 22 91 d3 01 00 74 29 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 54 1a 28 f9 65 8b 05 9d 23 d9 77
RSP: 0018:ffffc90015e7f828 EFLAGS: 00000286
RAX: 1ffffffff13f8d7d RBX: 0000000000000286 RCX: ffffffff815b7ef2
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286
RBP: ffff8880ae4255c0 R08: 0000000000000001 R09: ffffffff8d0c0a67
R10: fffffbfff1a1814c R11: 0000000000000000 R12: 0000000100049000
R13: ffff8880ae4255c0 R14: 0000000000000001 R15: 0000000000000014
 __mod_timer+0x837/0xe30 kernel/time/timer.c:1066
 sk_reset_timer+0x1f/0xc0 net/core/sock.c:2952
 tcp_rearm_rto+0xce/0xf0 net/ipv4/tcp_input.c:3027
 tcp_event_new_data_sent+0x31c/0x3e0 net/ipv4/tcp_output.c:81
 tcp_write_xmit+0xee2/0x5c90 net/ipv4/tcp_output.c:2534
 __tcp_push_pending_frames+0xaa/0x330 net/ipv4/tcp_output.c:2705
 tcp_send_fin+0x117/0xbb0 net/ipv4/tcp_output.c:3262
 tcp_close+0xb3a/0x1210 net/ipv4/tcp.c:2492
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 __sock_release net/socket.c:596 [inline]
 sock_release+0x87/0x1b0 net/socket.c:624
 rds_tcp_conn_path_shutdown+0x1e5/0x3f0 net/rds/tcp_connect.c:216
 rds_conn_shutdown+0x23e/0x922 net/rds/connection.c:386
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Kernel Offset: disabled
Rebooting in 86400 seconds..