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lockdep bfs error:-1
WARNING: CPU: 0 PID: 16844 at kernel/locking/lockdep.c:1960 print_bfs_bug+0x130/0x1e0 kernel/locking/lockdep.c:1960
Modules linked in:
CPU: 0 PID: 16844 Comm: syz-executor.1 Not tainted 5.9.0-rc7-next-20200930-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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:ffffc900075075c8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815df1a5 RDI: fffff52000ea0eab
RBP: 00000000ffffffff R08: 0000000000000001 R09: ffff8880ae420f8b
R10: 0000000000000000 R11: 207065646b636f6c R12: ffff888093f38580
R13: dffffc0000000000 R14: 0000000000000003 R15: 0000000000000000
FS:  00007ff1bd862700(0000) GS:ffff8880ae400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f086e1d2810 CR3: 000000009231d000 CR4: 00000000001506f0
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
 dentry_free+0xc3/0x160 fs/dcache.c:350
 __dentry_kill+0x4c6/0x640 fs/dcache.c:593
 dentry_kill fs/dcache.c:717 [inline]
 dput+0x635/0xbc0 fs/dcache.c:878
 find_next_child fs/libfs.c:263 [inline]
 simple_recursive_removal+0x271/0x6b0 fs/libfs.c:278
 debugfs_remove fs/debugfs/inode.c:725 [inline]
 debugfs_remove+0x59/0x80 fs/debugfs/inode.c:719
 blk_mq_debugfs_unregister_hctx+0x34/0xa0 block/blk-mq-debugfs.c:893
 blk_mq_exit_hw_queues block/blk-mq.c:2600 [inline]
 blk_mq_exit_queue+0x377/0x510 block/blk-mq.c:3257
 blk_cleanup_queue+0x13b/0x1e0 block/blk-core.c:398
 loop_remove drivers/block/loop.c:2193 [inline]
 loop_control_ioctl drivers/block/loop.c:2291 [inline]
 loop_control_ioctl+0x3e1/0x480 drivers/block/loop.c:2257
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45dd99
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff1bd861c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000012900 RCX: 000000000045dd99
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000006
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fff2c5f6d2f R14: 00007ff1bd8629c0 R15: 000000000118bf2c