INFO: task syz-executor.5:24024 blocked for more than 140 seconds. Not tainted 4.14.120 #14 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29184 24024 7160 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 SYSC_acct kernel/acct.c:285 [inline] SyS_acct+0x68/0x870 kernel/acct.c:273 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x458da9 RSP: 002b:00007fd7dad5bc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd7dad5c6d4 R13: 00000000004beccc R14: 00000000004cfc70 R15: 00000000ffffffff INFO: task syz-executor.5:24027 blocked for more than 140 seconds. Not tainted 4.14.120 #14 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29232 24027 24024 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 SYSC_acct kernel/acct.c:285 [inline] SyS_acct+0x68/0x870 kernel/acct.c:273 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x458da9 RSP: 002b:00007fd7dad5bc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd7dad5c6d4 R13: 00000000004beccc R14: 00000000004cfc70 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1009: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4541 2 locks held by getty/7115: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7116: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7117: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7118: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7119: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7120: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7121: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/23924: #0: (acct_on_mutex){+.+.}, at: [] SYSC_acct kernel/acct.c:285 [inline] #0: (acct_on_mutex){+.+.}, at: [] SyS_acct+0x68/0x870 kernel/acct.c:273 1 lock held by syz-executor.5/24024: #0: (acct_on_mutex){+.+.}, at: [] SYSC_acct kernel/acct.c:285 [inline] #0: (acct_on_mutex){+.+.}, at: [] SyS_acct+0x68/0x870 kernel/acct.c:273 1 lock held by syz-executor.5/24027: #0: (acct_on_mutex){+.+.}, at: [] SYSC_acct kernel/acct.c:285 [inline] #0: (acct_on_mutex){+.+.}, at: [] SyS_acct+0x68/0x870 kernel/acct.c:273 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1009 Comm: khungtaskd Not tainted 4.14.120 #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:402 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7402 Comm: kworker/u4:5 Not tainted 4.14.120 #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880908fc600 task.stack: ffff8880664a0000 RIP: 0010:__lock_acquire+0x494/0x45e0 kernel/locking/lockdep.c:3432 RSP: 0018:ffff8880664a7ab0 EFLAGS: 00000002 RAX: 000000000000002a RBX: 0000000000000000 RCX: 0000000000020000 RDX: 1ffff1101211f9de RSI: 1ffff1101211f9d9 RDI: ffff8880908fcef4 RBP: ffff8880664a7c60 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8880908fced0 R11: ffff8880908fc600 R12: ffffffff8778f2a0 R13: 000000000000002a R14: 0000000000000002 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fde10fa8000 CR3: 000000009b749000 CR4: 00000000001406f0 Call Trace: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991 rcu_lock_acquire include/linux/rcupdate.h:244 [inline] rcu_read_lock include/linux/rcupdate.h:631 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x107/0x6d0 net/batman-adv/network-coding.c:726 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:402 Code: e0 0d 81 e1 00 00 03 00 41 c1 e1 13 09 c3 41 8b 42 20 48 c1 ea 03 09 d9 44 89 c3 c1 e3 12 81 e3 00 00 04 00 09 d9 25 ff 1f 00 00 <41> 09 c9 8b 4d 20 c1 e1 14 41 09 c9 41 09 c1 48 b8 00 00 00 00