====================================================== WARNING: possible circular locking dependency detected 5.10.215 #1 Not tainted ------------------------------------------------------ syz-executor.7/14786 is trying to acquire lock: ffff888017db8b78 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}, at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: ffffffff8561aca8 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (rfkill_global_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 rfkill_register+0x36/0xa10 net/rfkill/core.c:1016 hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3774 __vhci_create_device+0x2c8/0x5c0 drivers/bluetooth/hci_vhci.c:129 vhci_create_device drivers/bluetooth/hci_vhci.c:153 [inline] vhci_open_timeout+0x38/0x50 drivers/bluetooth/hci_vhci.c:310 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299 -> #3 (&data->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 vhci_send_frame+0x63/0xa0 drivers/bluetooth/hci_vhci.c:71 hci_send_frame+0x1b9/0x320 net/bluetooth/hci_core.c:4061 hci_sched_acl_pkt net/bluetooth/hci_core.c:4586 [inline] hci_sched_acl net/bluetooth/hci_core.c:4671 [inline] hci_tx_work+0x10af/0x1660 net/bluetooth/hci_core.c:4742 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299 -> #2 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}: __flush_work+0x105/0xa90 kernel/workqueue.c:3053 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 hci_dev_close+0x175/0x1d0 net/bluetooth/hci_core.c:1865 hci_sock_ioctl+0x288/0x980 net/bluetooth/hci_sock.c:1067 sock_do_ioctl+0xd3/0x300 net/socket.c:1066 sock_ioctl+0x3ea/0x700 net/socket.c:1206 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+0x19a/0x210 fs/ioctl.c:739 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xcc -> #1 (&hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 hci_req_sync net/bluetooth/hci_request.c:275 [inline] bg_scan_update+0x82/0x500 net/bluetooth/hci_request.c:2895 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299 -> #0 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3438 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 CPU: 1 PID: 14790 Comm: syz-executor.6 Not tainted 5.10.215 #1 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 Call Trace: vfs_write+0x29a/0xa70 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xcc fail_dump lib/fault-inject.c:52 [inline] should_fail.cold+0x5/0xa lib/fault-inject.c:146 other info that might help us debug this: Chain exists of: (work_completion)(&hdev->bg_scan_update) --> should_failslab+0x5/0x20 mm/slab_common.c:1193 &data->open_mutex --> slab_pre_alloc_hook mm/slab.h:515 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2904 [inline] kmem_cache_alloc_trace+0x55/0x320 mm/slub.c:2921 rfkill_global_mutex kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] wakeup_source_device_create+0x46/0x2b0 drivers/base/power/wakeup_stats.c:142 Possible unsafe locking scenario: CPU0 CPU1 wakeup_source_sysfs_add+0x1a/0xa0 drivers/base/power/wakeup_stats.c:181 ---- ---- lock( wakeup_source_register+0x9d/0x130 drivers/base/power/wakeup.c:228 rfkill_global_mutex); ep_create_wakeup_source+0x1c4/0x2b0 fs/eventpoll.c:1463 lock(&data->open_mutex ); lock( rfkill_global_mutex); lock((work_completion)(&hdev->bg_scan_update) ep_insert fs/eventpoll.c:1525 [inline] do_epoll_ctl+0x1f1d/0x2c00 fs/eventpoll.c:2269 ); *** DEADLOCK *** 1 lock held by syz-executor.7/14786: #0: ffffffff8561aca8 ( rfkill_global_mutex){+.+.}-{3:3} , at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 stack backtrace: __do_sys_epoll_ctl fs/eventpoll.c:2322 [inline] __se_sys_epoll_ctl fs/eventpoll.c:2313 [inline] __x64_sys_epoll_ctl+0x13f/0x1c0 fs/eventpoll.c:2313 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xcc RIP: 0033:0x7fc211b81b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc20f0f7188 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 RAX: ffffffffffffffda RBX: 00007fc211c94f60 RCX: 00007fc211b81b19 RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000004 RBP: 00007fc20f0f71d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000200 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff1e4e4e3f R14: 00007fc20f0f7300 R15: 0000000000022000 CPU: 0 PID: 14786 Comm: syz-executor.7 Not tainted 5.10.215 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 check_noncircular+0x263/0x2e0 kernel/locking/lockdep.c:2123 check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3438 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 vfs_write+0x29a/0xa70 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xcc RIP: 0033:0x7f8a6e4e5b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8a6ba5b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8a6e5f8f60 RCX: 00007f8a6e4e5b19 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007f8a6e53ff6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffecd80e1df R14: 00007f8a6ba5b300 R15: 0000000000022000 rfkill: input handler enabled rfkill: input handler disabled rfkill: input handler enabled