IPVS: stopping master sync thread 10526 ...
INFO: task syz-executor1:16807 blocked for more than 140 seconds.
      Not tainted 4.9.120-gf85543b #24
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor1   D28520 16807   3875 0x00000004
 ffff88019976c800 0000000000000000 ffff8801c3785f80 ffff88019cd41800
 ffff8801db321c18 ffff88019bddfac8 ffffffff839eedcd ffffffff81237347
 0000000000000000 ffff88019976d0c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839f03cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839fba08>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839fba08>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81eec337>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff8122df70>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff8122df70>] down_write_nested+0x60/0xa0 kernel/locking/rwsem.c:174
 [<ffffffff815acfca>] inode_lock_nested include/linux/fs.h:801 [inline]
 [<ffffffff815acfca>] filename_create+0x17a/0x490 fs/namei.c:3639
 [<ffffffff815af6a1>] user_path_create fs/namei.c:3697 [inline]
 [<ffffffff815af6a1>] SYSC_mkdirat fs/namei.c:3841 [inline]
 [<ffffffff815af6a1>] SyS_mkdirat fs/namei.c:3833 [inline]
 [<ffffffff815af6a1>] SYSC_mkdir fs/namei.c:3860 [inline]
 [<ffffffff815af6a1>] SyS_mkdir+0xb1/0x260 fs/namei.c:3858
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839ffcd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813684dc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813684dc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81427d48>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3778:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fde72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82123d42>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor1/16749:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] do_last fs/namei.c:3312 [inline]
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] path_openat+0xed5/0x3590 fs/namei.c:3534
2 locks held by syz-executor1/16807:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#19/1){+.+.+.}, at: [<ffffffff815acfca>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#19/1){+.+.+.}, at: [<ffffffff815acfca>] filename_create+0x17a/0x490 fs/namei.c:3639
1 lock held by syz-executor1/16810:
 #0:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815e481c>] inode_lock include/linux/fs.h:766 [inline]
 #0:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815e481c>] lock_mount+0x8c/0x2c0 fs/namespace.c:2101
2 locks held by syz-executor1/16813:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff815e38ef>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] do_last fs/namei.c:3312 [inline]
 #1:  (&sb->s_type->i_mutex_key#19){++++++}, at: [<ffffffff815a7da5>] path_openat+0xed5/0x3590 fs/namei.c:3534

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.120-gf85543b #24
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d963fd08 ffffffff81eb8049 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d963fd40
 ffffffff81ec3357 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb8049>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb8049>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec3357>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec32ea>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810ba0a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81368a74>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81368a74>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368a74>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368a74>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ee0d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839ffe9c>] 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 skipped: idling at pc 0xffffffff839fe8d6