Hello, syzbot found the following issue on: HEAD commit: 38a288f5941e Add linux-next specific files for 20220506 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=10e9fd3ef00000 kernel config: https://syzkaller.appspot.com/x/.config?x=6f4fbf50aa82985b dashboard link: https://syzkaller.appspot.com/bug?extid=e68a3899a8927b14f863 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=111555fef00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1629b3eaf00000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e68a3899a8927b14f863@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/u5:1:3738 blocked for more than 143 seconds. Not tainted 5.18.0-rc5-next-20220506-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u5:1 state:D stack:27952 pid: 3738 ppid: 2 flags:0x00004000 Workqueue: hci0 hci_power_on Call Trace: <TASK> context_switch kernel/sched/core.c:5109 [inline] __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6424 schedule+0xd2/0x1f0 kernel/sched/core.c:6496 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6555 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747 hci_dev_do_open+0x2a/0x70 net/bluetooth/hci_core.c:480 hci_power_on+0x133/0x630 net/bluetooth/hci_core.c:963 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 </TASK> INFO: task syz-executor271:4065 blocked for more than 143 seconds. Not tainted 5.18.0-rc5-next-20220506-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor271 state:D stack:27952 pid: 4065 ppid: 3735 flags:0x00004002 Call Trace: <TASK> context_switch kernel/sched/core.c:5109 [inline] __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6424 schedule+0xd2/0x1f0 kernel/sched/core.c:6496 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1883 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x378/0x530 kernel/sched/completion.c:106 __flush_work+0x56c/0xb10 kernel/workqueue.c:3098 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3185 hci_dev_close_sync+0x8d/0x1150 net/bluetooth/hci_sync.c:4092 hci_dev_do_close+0x32/0x70 net/bluetooth/hci_core.c:553 hci_unregister_dev+0x1c4/0x550 net/bluetooth/hci_core.c:2685 hci_uart_tty_close+0x241/0x2a0 drivers/bluetooth/hci_ldisc.c:548 tty_ldisc_close+0x110/0x190 drivers/tty/tty_ldisc.c:456 tty_ldisc_kill+0x94/0x150 drivers/tty/tty_ldisc.c:608 tty_ldisc_release+0xe1/0x2a0 drivers/tty/tty_ldisc.c:776 tty_release_struct+0x20/0xe0 drivers/tty/tty_io.c:1694 tty_release+0xc70/0x1200 drivers/tty/tty_io.c:1865 __fput+0x277/0x9d0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:177 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xaff/0x2a00 kernel/exit.c:795 do_group_exit+0xd2/0x2f0 kernel/exit.c:925 __do_sys_exit_group kernel/exit.c:936 [inline] __se_sys_exit_group kernel/exit.c:934 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:934 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd7dadc9c69 RSP: 002b:00007ffe0ae022a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fd7dae363d0 RCX: 00007fd7dadc9c69 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 00007ffe0ae02320 R10: 00007ffe0ae02320 R11: 0000000000000246 R12: 00007fd7dae363d0 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 </TASK> Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8bd84f50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:502 1 lock held by rcu_tasks_trace/13: #0: ffffffff8bd84bd0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:502 1 lock held by khungtaskd/29: #0: ffffffff8bd85aa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491 2 locks held by getty/3366: #0: ffff888024cd1098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002ce62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2118 3 locks held by kworker/u5:1/3738: #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888019af7138 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000323fda8 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffff88807ec49048 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_open+0x2a/0x70 net/bluetooth/hci_core.c:480 3 locks held by syz-executor271/4065: #0: ffff88801d49b098 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:290 [inline] #0: ffff88801d49b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:336 [inline] #0: ffff88801d49b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:367 [inline] #0: ffff88801d49b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x15c/0x2a0 drivers/tty/tty_ldisc.c:775 #1: ffff88801d49c098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:296 [inline] #1: ffff88801d49c098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:338 [inline] #1: ffff88801d49c098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:367 [inline] #1: ffff88801d49c098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0x20f/0x2a0 drivers/tty/tty_ldisc.c:775 #2: ffff88807ec49048 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x2a/0x70 net/bluetooth/hci_core.c:551 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 5.18.0-rc5-next-20220506-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xc22/0xf90 kernel/hung_task.c:378 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:554 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
