INFO: task syz-executor.4:12395 blocked for more than 143 seconds. Not tainted 5.19.0-syzkaller-02972-g200e340f2196 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27848 pid:12395 ppid: 3715 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5178 [inline] __schedule+0xa00/0x4c10 kernel/sched/core.c:6490 schedule+0xda/0x1b0 kernel/sched/core.c:6566 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6625 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747 tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] tty_open+0x552/0xff0 drivers/tty/tty_io.c:2133 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4a1/0x12d0 fs/open.c:878 do_open fs/namei.c:3499 [inline] path_openat+0x1c92/0x28f0 fs/namei.c:3632 do_filp_open+0x1b6/0x400 fs/namei.c:3659 do_sys_openat2+0x16d/0x4c0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1337 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+0x63/0xcd RIP: 0033:0x7f316e03c194 RSP: 002b:00007f316cfbbca0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f316e19c120 RCX: 00007f316e03c194 RDX: 0000000000000002 RSI: 00007f316cfbbd40 RDI: 00000000ffffff9c RBP: 00007f316cfbbd40 R08: 0000000000000000 R09: 000000000000000d R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 00007f316e6cfb1f R14: 00007f316cfbc300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8bd86870 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8bd86570 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8bd873c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6492 2 locks held by getty/3278: #0: ffff888026e6f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002d162e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2124 2 locks held by kworker/u4:5/11794: 3 locks held by syz-executor.3/12357: 1 lock held by syz-executor.4/12395: #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x552/0xff0 drivers/tty/tty_io.c:2133 1 lock held by syz-executor.4/12525: #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x552/0xff0 drivers/tty/tty_io.c:2133 1 lock held by syz-executor.4/12581: #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] #0: ffffffff8c7fb128 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x552/0xff0 drivers/tty/tty_io.c:2133 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 5.19.0-syzkaller-02972-g200e340f2196 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __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:212 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:369 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11794 Comm: kworker/u4:5 Not tainted 5.19.0-syzkaller-02972-g200e340f2196 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: bat_events batadv_nc_worker RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4582 [inline] RIP: 0010:__lock_acquire+0x9cc/0x5660 kernel/locking/lockdep.c:5037 Code: 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 52 3a 00 00 49 8d 7c 24 21 0f b6 5b 21 48 b8 00 00 00 00 00 fc ff df <48> 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 RSP: 0018:ffffc90002d4fa38 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000000007 RCX: ffffffff815e45dc RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88802759e369 RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000002 R10: fffffbfff20d1d28 R11: 0000000000000001 R12: ffff88802759e348 R13: ffff88802759d880 R14: 0000000000000000 R15: f945de6ec35eab72 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c001833000 CR3: 000000000ba8e000 CR4: 00000000003506f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 rcu_lock_acquire include/linux/rcupdate.h:280 [inline] rcu_read_lock include/linux/rcupdate.h:706 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719 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:306