INFO: task syz-executor.2:14922 can't die for more than 143 seconds. syz-executor.2 R running task 28128 14922 8829 0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1047: #0: 000000003695fab9 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5262 1 lock held by udevd/3883: 1 lock held by rsyslogd/8692: #0: 00000000fd41217c (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8782: #0: 00000000e7c6a165 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d69f9c3f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8783: #0: 0000000002ac0129 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000318258b0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8784: #0: 000000000d7ef31c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e58fa54e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8785: #0: 00000000729c901c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002ca1cf86 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8786: #0: 00000000baa156a0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000019a8a51 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8787: #0: 0000000005b42fba (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e208e503 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8788: #0: 00000000bfd54196 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000907e8cf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/14922: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1047 Comm: khungtaskd Not tainted 5.2.0-rc4-next-20190612 #13 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15472 Comm: kworker/u4:6 Not tainted 5.2.0-rc4-next-20190612 #13 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:match_held_lock+0x12/0x510 kernel/locking/lockdep.c:3943 Code: d2 88 89 45 84 e8 7e 0a 53 00 8b 45 84 e9 67 ff ff ff 66 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 57 41 56 <41> 55 41 54 53 48 89 fb 48 83 c7 10 48 89 fa 48 83 ec 08 48 c1 ea RSP: 0018:ffff88805d317b98 EFLAGS: 00000096 RAX: dffffc0000000000 RBX: 0000000000000003 RCX: ffff88805d317c68 RDX: 0000000000000003 RSI: ffffffff88da3c80 RDI: ffff8880907d4a20 RBP: ffff88805d317ba8 R08: ffff8880907d4140 R09: 0000000000000003 R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: ffff8880907d4a20 R13: ffffffff87078e9a R14: ffffffff88da3c80 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a1b47000 CR4: 00000000001406e0 Call Trace: find_held_lock+0x35/0x130 kernel/locking/lockdep.c:3988 __lock_release kernel/locking/lockdep.c:4172 [inline] lock_release+0x277/0xa50 kernel/locking/lockdep.c:4437 rcu_lock_release include/linux/rcupdate.h:213 [inline] rcu_read_unlock include/linux/rcupdate.h:647 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x225/0x760 net/batman-adv/network-coding.c:718 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