INFO: task syz-executor.3:14354 can't die for more than 143 seconds. syz-executor.3 R running task 26824 14354 8856 0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1064: #0: ffffffff88fa7f00 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/8718: #0: ffff888096fdce20 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8808: #0: ffff8880a7e48e90 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8809: #0: ffff8880a93fd750 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8810: #0: ffff8880a6e53790 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8811: #0: ffff8880a7e48610 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8812: #0: ffff8880a7e49710 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8813: #0: ffff8880a8599190 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8814: #0: ffff8880a8fd64d0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by kworker/1:3/3523: #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880aa435ba8 ((wq_completion)rcu_gp){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff88809a6cfdc0 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 1 lock held by syz-executor.3/14354: #0: ffffffff88fabcb8 (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:285 [inline] #0: ffffffff88fabcb8 (rcu_state.exp_mutex){+.+.}, at: synchronize_rcu_expedited+0x4d6/0x5f0 kernel/rcu/tree_exp.h:817 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1064 Comm: khungtaskd Not tainted 5.3.0-rc6-next-20190827 #74 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+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:269 [inline] watchdog+0xc99/0x1360 kernel/hung_task.c:353 kthread+0x361/0x430 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: 3032 Comm: kworker/u4:5 Not tainted 5.3.0-rc6-next-20190827 #74 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_memory_region+0x1d/0x1a0 mm/kasan/generic.c:191 Code: 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 48 85 f6 0f 84 34 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 55 0f b6 d2 48 39 c7 48 89 e5 <41> 55 41 54 53 0f 86 07 01 00 00 4c 8d 5c 37 ff 49 89 f8 48 b8 00 RSP: 0018:ffff88809f52fab8 EFLAGS: 00000012 RAX: ffff7fffffffffff RBX: 0000000000000029 RCX: ffffffff8157f632 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8a769960 RBP: ffff88809f52fab8 R08: 0000000000000000 R09: 0000000000000029 R10: ffff88809f50cb30 R11: ffff88809f50c240 R12: 0000000000000008 R13: ffff88809f50cb30 R14: 0000000000000000 R15: 0000000000020029 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000021000000 CR3: 000000009a267000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kasan_check_read+0x11/0x20 mm/kasan/common.c:92 test_bit include/asm-generic/bitops-instrumented.h:237 [inline] hlock_class kernel/locking/lockdep.c:163 [inline] mark_lock+0xc2/0x1220 kernel/locking/lockdep.c:3643 mark_usage kernel/locking/lockdep.c:3592 [inline] __lock_acquire+0x538/0x4a00 kernel/locking/lockdep.c:3909 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 rcu_lock_acquire include/linux/rcupdate.h:208 [inline] rcu_read_lock include/linux/rcupdate.h:599 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x117/0x760 net/batman-adv/network-coding.c:718 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352