====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0 Not tainted ------------------------------------------------------ syz-executor/5776 is trying to acquire lock: ffff88807d6ca148 ((wq_completion)hci1#2){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x6e/0x120 kernel/workqueue.c:3875 but task is already holding lock: ffff888060a68d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:481 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 hci_acldata_packet net/bluetooth/hci_core.c:3792 [inline] hci_rx_work+0xabf/0x1650 net/bluetooth/hci_core.c:4033 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #1 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}: process_one_work+0x927/0x1b40 kernel/workqueue.c:3207 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 ((wq_completion)hci1#2){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 touch_wq_lockdep_map+0x78/0x120 kernel/workqueue.c:3875 __flush_workqueue+0x129/0x1200 kernel/workqueue.c:3917 drain_workqueue+0x18f/0x3d0 kernel/workqueue.c:4081 hci_dev_close_sync+0x333/0x1110 net/bluetooth/hci_sync.c:5181 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:483 hci_unregister_dev+0x213/0x620 net/bluetooth/hci_core.c:2698 vhci_release+0x7f/0x100 drivers/bluetooth/hci_vhci.c:664 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: (wq_completion)hci1#2 --> (work_completion)(&hdev->rx_work) --> &hdev->req_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hdev->req_lock); lock((work_completion)(&hdev->rx_work)); lock(&hdev->req_lock); lock((wq_completion)hci1#2); *** DEADLOCK *** 1 lock held by syz-executor/5776: #0: ffff888060a68d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:481 stack backtrace: CPU: 0 UID: 0 PID: 5776 Comm: syz-executor Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2186 check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 touch_wq_lockdep_map+0x78/0x120 kernel/workqueue.c:3875 __flush_workqueue+0x129/0x1200 kernel/workqueue.c:3917 drain_workqueue+0x18f/0x3d0 kernel/workqueue.c:4081 hci_dev_close_sync+0x333/0x1110 net/bluetooth/hci_sync.c:5181 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:483 hci_unregister_dev+0x213/0x620 net/bluetooth/hci_core.c:2698 vhci_release+0x7f/0x100 drivers/bluetooth/hci_vhci.c:664 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc96277bb8a Code: Unable to access opcode bytes at 0x7fc96277bb60. RSP: 002b:00007ffc87843a70 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fc96277bb8a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffc87843abc R08: 00007ffc878433cc R09: 00007ffc878437d7 R10: 00007ffc87843450 R11: 0000000000000293 R12: 0000000000000032 R13: 0000000000045913 R14: 00000000000458e1 R15: 00007ffc87843b10