INFO: task syz-executor.2:15389 can't die for more than 143 seconds. syz-executor.2 R running task 25880 15389 18649 0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1045: #0: 00000000ac7f8d5a (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5262 1 lock held by rsyslogd/9006: #0: 00000000403b1d8f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9096: #0: 00000000722865e2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006c8ed22d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9097: #0: 00000000a82f69f4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001aea09f5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9098: #0: 000000004d4b2278 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f9b0872f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9099: #0: 000000009c963ee1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000012cd5865 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9100: #0: 0000000084ad47fb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000079623ef9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9101: #0: 000000006b528358 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006fb707dc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9102: #0: 00000000f0408d30 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005f6fcc9a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 4 locks held by syz-executor.2/15389: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1045 Comm: khungtaskd Not tainted 5.2.0-rc4-next-20190614 #15 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:249 [inline] watchdog+0xb88/0x12b0 kernel/hung_task.c:333 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11165 Comm: kworker/u4:14 Not tainted 5.2.0-rc4-next-20190614 #15 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:preempt_latency_start kernel/sched/core.c:3159 [inline] RIP: 0010:preempt_latency_start kernel/sched/core.c:3154 [inline] RIP: 0010:preempt_count_add+0xe6/0x1b0 kernel/sched/core.c:3182 Code: 85 c0 75 39 65 4c 8b 24 25 c0 fd 01 00 49 8d bc 24 c8 11 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 ab 00 00 00 49 89 9c 24 c8 11 00 00 5b 41 5c 5d c3 48 8b 45 RSP: 0018:ffff888056a2faf8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff81607eb6 RCX: 0000000000000000 RDX: 1ffff1100ad3da41 RSI: 0000000000000000 RDI: ffff8880569ed208 RBP: ffff888056a2fb08 R08: ffff8880569ec040 R09: 0000000000000003 R10: ffffed1015d06bdf R11: ffff8880ae835efb R12: ffff8880569ec040 R13: 0000000000000086 R14: ffff88805396afc0 R15: ffffed100a72d5fc FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000058b40000 CR4: 00000000001406f0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0x79/0xcd kernel/locking/spinlock.c:159 lock_timer_base+0x56/0x1b0 kernel/time/timer.c:932 __mod_timer kernel/time/timer.c:1004 [inline] mod_timer kernel/time/timer.c:1096 [inline] add_timer+0x108/0x930 kernel/time/timer.c:1132 __queue_delayed_work+0x1af/0x270 kernel/workqueue.c:1649 queue_delayed_work_on+0x19a/0x200 kernel/workqueue.c:1674 queue_delayed_work include/linux/workqueue.h:509 [inline] batadv_nc_start_timer net/batman-adv/network-coding.c:79 [inline] batadv_nc_worker+0x46c/0x760 net/batman-adv/network-coding.c:740 process_one_work+0x989/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352