INFO: task syz-executor862:15496 blocked for more than 140 seconds. Not tainted 4.14.158-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor862 D28528 15496 7131 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __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 tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 paste_selection+0x106/0x3f2 drivers/tty/vt/selection.c:349 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7ee4 R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor862:15497 blocked for more than 140 seconds. Not tainted 4.14.158-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor862 D28528 15497 7130 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __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 tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 paste_selection+0x106/0x3f2 drivers/tty/vt/selection.c:349 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7ef3 R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor862:15498 blocked for more than 140 seconds. Not tainted 4.14.158-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor862 D28528 15498 7133 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __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 tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 paste_selection+0x106/0x3f2 drivers/tty/vt/selection.c:349 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7f02 R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor862:15500 blocked for more than 140 seconds. Not tainted 4.14.158-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor862 D28528 15500 7129 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __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 tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 paste_selection+0x106/0x3f2 drivers/tty/vt/selection.c:349 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7f03 R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor862:15501 blocked for more than 140 seconds. Not tainted 4.14.158-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor862 D28528 15501 7132 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __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 tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 paste_selection+0x106/0x3f2 drivers/tty/vt/selection.c:349 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7f0b R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1045: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/6979: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7103: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7104: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7105: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7106: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7107: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7108: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor862/15496: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 2 locks held by syz-executor862/15497: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 2 locks held by syz-executor862/15498: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 2 locks held by syz-executor862/15499: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 2 locks held by syz-executor862/15500: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 2 locks held by syz-executor862/15501: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&buf->lock){+.+.}, at: [] tty_buffer_lock_exclusive+0x1f/0x30 drivers/tty/tty_buffer.c:60 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1045 Comm: khungtaskd Not tainted 4.14.158-syzkaller #0 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+0x142/0x197 lib/dump_stack.c:58 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:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15499 Comm: syz-executor862 Not tainted 4.14.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888093c62600 task.stack: ffff888097c98000 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:360 [inline] RIP: 0010:rcu_is_watching+0x10/0xb0 kernel/rcu/tree.c:1130 RSP: 0018:ffff888097c9f760 EFLAGS: 00000082 RAX: 0000000000000001 RBX: ffffffff88337c00 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffff8880aed2b558 RDI: ffff888093c62e7c RBP: ffff888097c9f770 R08: 000000c91a25ed84 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: ffff8880aed2b5e0 R13: ffff888093c62600 R14: ffff888093c626d0 R15: 00000000000009d0 FS: 00000000019ee880(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7107eeb000 CR3: 00000000967e6000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_sched_held+0x8e/0x130 kernel/rcu/update.c:111 trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] update_curr+0x53c/0x6a0 kernel/sched/fair.c:855 pick_next_task_fair+0x661/0x1430 kernel/sched/fair.c:6295 pick_next_task kernel/sched/core.c:3232 [inline] __schedule+0x43e/0x1cd0 kernel/sched/core.c:3357 schedule+0x92/0x1c0 kernel/sched/core.c:3428 paste_selection+0x293/0x3f2 drivers/tty/vt/selection.c:355 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441319 RSP: 002b:00007ffce96f8578 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441319 RDX: 0000000020000040 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00000000000a7f00 R08: 000000000000000d R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402090 R13: 0000000000402120 R14: 0000000000000000 R15: 0000000000000000 Code: 48 83 c4 08 5b 5d c3 48 89 45 f0 e8 db e0 39 00 48 8b 45 f0 eb cb 0f 1f 44 00 00 55 48 89 e5 53 48 83 ec 08 65 ff 05 e0 f1 b3 7e bb f5 bc 01 48 c7 c3 40 39 02 00 48 ba 00 00 00 00 00 fc ff