Hello, syzbot found the following issue on: HEAD commit: 8de1e7afcc1c Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=1753c55b680000 kernel config: https://syzkaller.appspot.com/x/.config?x=3e6feaeda5dcbc27 dashboard link: https://syzkaller.appspot.com/bug?extid=47d22a47f6bd21399c93 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/0f00907f9764/disk-8de1e7af.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0502fe78c60d/vmlinux-8de1e7af.xz kernel image: https://storage.googleapis.com/syzbot-assets/192135168cc0/Image-8de1e7af.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+47d22a47f6bd21399c93@xxxxxxxxxxxxxxxxxxxxxxxxx Bluetooth: hci5: hardware error 0x00 ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0 Not tainted ------------------------------------------------------ kworker/u5:3/6132 is trying to acquire lock: ffff0000d5a40dc0 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}, at: __flush_work+0xd0/0x1c0 kernel/workqueue.c:3403 but task is already holding lock: ffff0000d5a410b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] ffff0000d5a410b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_error_reset+0xec/0x248 net/bluetooth/hci_core.c:1059 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] hci_rfkill_set_block+0xe8/0x20c net/bluetooth/hci_core.c:956 rfkill_set_block+0x18c/0x37c net/rfkill/core.c:346 rfkill_fop_write+0x578/0x734 net/rfkill/core.c:1305 vfs_write+0x2a0/0x93c fs/read_write.c:582 ksys_write+0x15c/0x26c fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 -> #2 (rfkill_global_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 rfkill_register+0x44/0x7d4 net/rfkill/core.c:1075 hci_register_dev+0x3e0/0x954 net/bluetooth/hci_core.c:2656 __vhci_create_device drivers/bluetooth/hci_vhci.c:437 [inline] vhci_create_device+0x358/0x6c4 drivers/bluetooth/hci_vhci.c:478 vhci_get_user drivers/bluetooth/hci_vhci.c:535 [inline] vhci_write+0x318/0x3b8 drivers/bluetooth/hci_vhci.c:615 call_write_iter include/linux/fs.h:1956 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x628/0x93c fs/read_write.c:584 ksys_write+0x15c/0x26c fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 -> #1 (&data->open_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 vhci_send_frame+0x8c/0x10c drivers/bluetooth/hci_vhci.c:78 hci_send_frame+0x1c4/0x35c net/bluetooth/hci_core.c:3039 hci_sched_acl_pkt net/bluetooth/hci_core.c:3651 [inline] hci_sched_acl net/bluetooth/hci_core.c:3736 [inline] hci_tx_work+0xba0/0x18e4 net/bluetooth/hci_core.c:3835 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 -> #0 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 __flush_work+0xf8/0x1c0 kernel/workqueue.c:3403 flush_work+0x24/0x38 kernel/workqueue.c:3428 hci_dev_close_sync+0x1c8/0xf2c net/bluetooth/hci_sync.c:4982 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline] hci_error_reset+0xf4/0x248 net/bluetooth/hci_core.c:1059 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 other info that might help us debug this: Chain exists of: (work_completion)(&hdev->tx_work) --> rfkill_global_mutex --> &hdev->req_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hdev->req_lock); lock(rfkill_global_mutex); lock(&hdev->req_lock); lock((work_completion)(&hdev->tx_work)); *** DEADLOCK *** 3 locks held by kworker/u5:3/6132: #0: ffff0000d425d938 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work+0x560/0x1204 kernel/workqueue.c:2603 #1: ffff800096f07c20 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_one_work+0x5a0/0x1204 kernel/workqueue.c:2605 #2: ffff0000d5a410b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] #2: ffff0000d5a410b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_error_reset+0xec/0x248 net/bluetooth/hci_core.c:1059 stack backtrace: CPU: 1 PID: 6132 Comm: kworker/u5:3 Not tainted 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: hci5 hci_error_reset Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 __flush_work+0xf8/0x1c0 kernel/workqueue.c:3403 flush_work+0x24/0x38 kernel/workqueue.c:3428 hci_dev_close_sync+0x1c8/0xf2c net/bluetooth/hci_sync.c:4982 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline] hci_error_reset+0xf4/0x248 net/bluetooth/hci_core.c:1059 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 Bluetooth: hci5: Opcode 0x c03 failed: -110 --- This report is generated by a bot. 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