random: crng init done
INFO: task syz-executor3:18099 blocked for more than 120 seconds.
      Not tainted 4.9.70-g9542d2a #109
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D29424 18099   3542 0x00000004
 ffff8801d10d3000 ffff8801b5043480 ffff8801b4e979c0 ffff8801d98fb000
 ffff8801db321418 ffff8801b8a87740 ffffffff83898c3b ffff8801b8a87718
 ffffffff8123886f 00ffffff838a45aa ffff8801db321ce8 ffff8801db321d10
Call Trace:
 [<ffffffff8389a1df>] schedule+0x7f/0x1b0 kernel/sched/core.c:3550
 [<ffffffff838a46c0>] rwsem_down_read_failed+0x1e0/0x320 kernel/locking/rwsem-xadd.c:260
 [<ffffffff81dc3bb8>] call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 [<ffffffff838a3442>] __down_read arch/x86/include/asm/rwsem.h:65 [inline]
 [<ffffffff838a3442>] down_read+0x52/0xb0 kernel/locking/rwsem.c:24
 [<ffffffff8200a815>] set_termios+0xf5/0x670 drivers/tty/tty_ioctl.c:592
 [<ffffffff8200b6c1>] tty_mode_ioctl+0x931/0x9c0 drivers/tty/tty_ioctl.c:970
 [<ffffffff8200b7f0>] n_tty_ioctl_helper+0x40/0x360 drivers/tty/tty_ioctl.c:1161
 [<ffffffff81fff3b8>] n_tty_ioctl+0x148/0x2d0 drivers/tty/n_tty.c:2437
 [<ffffffff81ff81f3>] tty_ioctl+0x733/0x2170 drivers/tty/tty_io.c:2992
 [<ffffffff815aa7da>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff815aa7da>] do_vfs_ioctl+0x1aa/0x1140 fs/ioctl.c:679
 [<ffffffff815ab7ff>] SYSC_ioctl fs/ioctl.c:694 [inline]
 [<ffffffff815ab7ff>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 [<ffffffff838aa405>] entry_SYSCALL_64_fastpath+0x23/0xc6

Showing all locks held in the system:
2 locks held by khungtaskd/514:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe15>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe15>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.?..}, at: [<ffffffff812355e0>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
2 locks held by getty/3307:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838a8602>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82002084>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133
2 locks held by syz-executor3/18099:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838a8602>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&o_tty->termios_rwsem/1){++++..}, at: [<ffffffff8200a815>] set_termios+0xf5/0x670 drivers/tty/tty_ioctl.c:592
2 locks held by syz-executor3/18130:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838a8602>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&o_tty->termios_rwsem/1){++++..}, at: [<ffffffff8200a815>] set_termios+0xf5/0x670 drivers/tty/tty_ioctl.c:592

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

NMI backtrace for cpu 0
CPU: 0 PID: 514 Comm: khungtaskd Not tainted 4.9.70-g9542d2a #109
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d9657d00 ffffffff81d90a29 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810ba1a0 ffff8801d9657d38
 ffffffff81d9bb4d 0000000000000000 0000000000000000 ffff8801b8379c18
Call Trace:
 [<ffffffff81d90a29>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d90a29>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81d9bb4d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81d9bc87>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810ba294>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff813703e0>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff813703e0>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813703e0>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813703e0>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff811985ed>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838aa6aa>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18080 Comm: syz-executor3 Not tainted 4.9.70-g9542d2a #109
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801c702c800 task.stack: ffff8801c1848000
RIP: 0010:[<ffffffff813681e2>] 
c [<ffffffff813681e2>] __sanitizer_cov_trace_pc+0x12/0x60 kernel/kcov.c:64
RSP: 0018:ffff8801c184fb28  EFLAGS: 00000286
RAX: ffff8801c702c800 RBX: ffffc900046a5060 RCX: ffffc90000f39000
RDX: 0000000000010000 RSI: 000000001fce2d2e RDI: ffffc900046a6260
RBP: ffff8801c184fb28 R08: 1ffff10038e05a1a R09: 0000000000000000
R10: 0000000000000003 R11: ffff8801c702c800 R12: ffffc900046a4000
R13: 000000046d0e478c R14: 0000000020f28ffc R15: ffff8801d050f938
FS:  00007ff3867bf700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3922580580 CR3: 00000001ce4a7000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801c184fb78
c ffffffff81fff47c
c ffffffffffffffff
c 000000000000078b
c
 0000000000000000
c ffff8801d050f700
c 1ffff10038309f75
c 000000000000541b
c
 ffffffffffffffe7
c ffff8801cecef200
c ffff8801c184fd70
c ffffffff81ff81f3
c
Call Trace:
 [<ffffffff81fff47c>] inq_canon drivers/tty/n_tty.c:2411 [inline]
 [<ffffffff81fff47c>] n_tty_ioctl+0x20c/0x2d0 drivers/tty/n_tty.c:2431
 [<ffffffff81ff81f3>] tty_ioctl+0x733/0x2170 drivers/tty/tty_io.c:2992
 [<ffffffff815aa7da>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff815aa7da>] do_vfs_ioctl+0x1aa/0x1140 fs/ioctl.c:679
 [<ffffffff815ab7ff>] SYSC_ioctl fs/ioctl.c:694 [inline]
 [<ffffffff815ab7ff>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 [<ffffffff838aa405>] entry_SYSCALL_64_fastpath+0x23/0xc6
Code: 
c89 
cdf 
ce8 
cd2 
c28 
c1d 
c00 
ce9 
c29 
cff 
cff 
cff 
c66 
c2e 
c0f 
c1f 
c84 
c00 
c00 
c00 
c00 
c00 
c0f 
c1f 
c00 
c55 
c65 
c48 
c8b 
c04 
c25 
c40 
c55 
c01 
c00 
c48 
c85 
cc0 
c48 
c89 
ce5 
c74 
c1a 
c<65> 
c8b 
c15 
ce7 
cd2 
cca 
c7e 
c81 
ce2 
c00 
c01 
c1f 
c00 
c75 
c0b 
c8b 
c90 
c68 
c12 
c00 
c00 
c