binder: 13496:13502 ioctl c0306201 2000dfd0 returned -22
binder: BINDER_SET_CONTEXT_MGR already set
binder: 13496:13502 ioctl 40046207 0 returned -16
binder: 13496:13513 unknown command 1074029327
binder: 13496:13513 ioctl c0306201 2000dfd0 returned -22
INFO: task kworker/u4:7:5155 blocked for more than 120 seconds.
      Not tainted 4.9.94-g8683408 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:7    D25544  5155      2 0x00000000
Workqueue: events_unbound flush_to_ldisc
 ffff8801b68e8000 0000000000000000 ffff8801cca8ca80 ffff8801cf976000
 ffff8801db221b98 ffff88019bc076c8 ffffffff839e140d ffffffff812337e7
 0000000000000000 ffff8801b68e88c0 0000000600000007 ffff8801db222468
Call Trace:
 [<ffffffff839e2a0f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839ee048>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839ee048>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee4db7>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff839ebe1c>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff839ebe1c>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff8211a71d>] isig+0xbd/0x4c0 drivers/tty/n_tty.c:1100
 [<ffffffff8211b1c2>] n_tty_receive_signal_char+0x22/0xf0 drivers/tty/n_tty.c:1212
 [<ffffffff8211f3c1>] n_tty_receive_char_special+0x10e1/0x2860 drivers/tty/n_tty.c:1258
 [<ffffffff82122a8a>] n_tty_receive_buf_fast drivers/tty/n_tty.c:1579 [inline]
 [<ffffffff82122a8a>] __receive_buf drivers/tty/n_tty.c:1613 [inline]
 [<ffffffff82122a8a>] n_tty_receive_buf_common+0x18ea/0x2300 drivers/tty/n_tty.c:1711
 [<ffffffff821234d3>] n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1746
 [<ffffffff82128fdf>] tty_ldisc_receive_buf+0xaf/0x190 drivers/tty/tty_buffer.c:455
 [<ffffffff82129fe3>] receive_buf drivers/tty/tty_buffer.c:474 [inline]
 [<ffffffff82129fe3>] flush_to_ldisc+0x253/0x370 drivers/tty/tty_buffer.c:533
 [<ffffffff8118ae01>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff8118bbf6>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119ad2d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839f24dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373

Showing all locks held in the system:
2 locks held by khungtaskd/517:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646bc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646bc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423bb0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3772:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f04b2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211c622>] n_tty_read+0x202/0x16b0 drivers/tty/n_tty.c:2133
5 locks held by kworker/u4:7/5155:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118ad0e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118ad0e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118ad0e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118ad0e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&buf->work)){+.+...}, at: [<ffffffff8118ad48>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
 #2:  (&tty->ldisc_sem){++++++}, at: [<ffffffff821277a0>] tty_ldisc_ref+0x20/0x80 drivers/tty/tty_ldisc.c:297
 #3:  (&port->buf.lock/1){+.+...}, at: [<ffffffff82129e16>] flush_to_ldisc+0x86/0x370 drivers/tty/tty_buffer.c:505
 #4:  (&o_tty->termios_rwsem/1){++++..}, at: [<ffffffff8211a71d>] isig+0xbd/0x4c0 drivers/tty/n_tty.c:1100

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 517 Comm: khungtaskd Not tainted 4.9.94-g8683408 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d88bfd08 ffffffff81eb0aa9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b7d60 ffff8801d88bfd40
 ffffffff81ebbdd7 0000000000000001 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81eb0aa9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb0aa9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebbdd7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebbd6a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7e64>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364c54>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364c54>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364c54>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364c54>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ad2d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839f24dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13483 Comm: syz-executor4 Not tainted 4.9.94-g8683408 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801bd614800 task.stack: ffff88019c1e0000
RIP: 0010:[<ffffffff821184b8>] 
c [<ffffffff821184b8>] __process_echoes+0x5b8/0x780 drivers/tty/n_tty.c:733
RSP: 0018:ffff88019c1e78a8  EFLAGS: 00000246
RAX: 0000000000040000 RBX: ffffc90000f2e000 RCX: ffffc9000435b000
RDX: 0000000000040000 RSI: ffffffff821184b8 RDI: ffffc90000f2f737
RBP: ffff88019c1e7910 R08: ffff8801bd615138 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000005378464d8
R13: 0000000000000127 R14: dffffc0000000000 R15: 00000005378464d8
FS:  00007f38385e6700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20e0cd5140 CR3: 00000001c9470000 CR4: 0000000000160670
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffc90000f30270
c 0000000000001103
c ffffc90000f30278
c ffffed003ae20a05
c
 ffff8801d710502c
c ffffc90000f2e020
c 0000000000001f00
c ffff8801d7104c80
c
 ffffc90000f2e000
c ffff8801d7104c80
c 0000000000000127
c ffffc90000f30300
c
Call Trace:
 [<ffffffff82119e17>] commit_echoes+0x147/0x1b0 drivers/tty/n_tty.c:766
 [<ffffffff8211f044>] n_tty_receive_char_special+0xd64/0x2860 drivers/tty/n_tty.c:1286
 [<ffffffff82122a8a>] n_tty_receive_buf_fast drivers/tty/n_tty.c:1579 [inline]
 [<ffffffff82122a8a>] __receive_buf drivers/tty/n_tty.c:1613 [inline]
 [<ffffffff82122a8a>] n_tty_receive_buf_common+0x18ea/0x2300 drivers/tty/n_tty.c:1711
 [<ffffffff82123510>] n_tty_receive_buf+0x30/0x40 drivers/tty/n_tty.c:1740
 [<ffffffff8211397f>] tiocsti drivers/tty/tty_io.c:2305 [inline]
 [<ffffffff8211397f>] tty_ioctl+0xc8f/0x2270 drivers/tty/tty_io.c:2896
 [<ffffffff815b03dc>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff815b03dc>] file_ioctl fs/ioctl.c:493 [inline]
 [<ffffffff815b03dc>] do_vfs_ioctl+0x1ac/0x11a0 fs/ioctl.c:677
 [<ffffffff815b145f>] SYSC_ioctl fs/ioctl.c:694 [inline]
 [<ffffffff815b145f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f2313>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
cc1 
cea 
c03 
c80 
c3c 
c02 
c00 
c0f 
c85 
c47 
c01 
c00 
c00 
c8b 
c4d 
ccc 
c4c 
c8b 
c6b 
c20 
c29 
c4d 
cc8 
c49 
cbe 
c00 
c00 
c00 
c00 
c00 
cfc 
cff 
cdf 
ceb 
c03 
c4d 
c89 
cfc 
ce8 
c18 
c45 
c24 
cff 
c<4c> 
c89 
ce8 
c4c 
c29 
ce0 
c48 
c3d 
cdf 
c0e 
c00 
c00 
c0f 
c86 
ced 
cfb 
cff 
cff 
ce8 
c01 
c45 
c