IPVS: Creating netns size=2536 id=33
INFO: task syz-executor3:15400 blocked for more than 140 seconds.
      Not tainted 4.9.113-g47bbcd6 #10
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D28656 15400   3864 0x00000004
 ffff88019fbd0000 0000000000000000 ffff8801d4698fc0 ffff8801d9a6b000
 ffff8801db321c18 ffff8801ba23fab8 ffffffff839e909d ffffffff81235647
 0000000000000000 ffff88019fbd08c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ea69f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839f5cd8>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f5cd8>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee7587>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff8122c270>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff8122c270>] down_write_nested+0x60/0xa0 kernel/locking/rwsem.c:174
 [<ffffffff815aa01a>] inode_lock_nested include/linux/fs.h:801 [inline]
 [<ffffffff815aa01a>] filename_create+0x17a/0x490 fs/namei.c:3639
 [<ffffffff815aca46>] user_path_create fs/namei.c:3697 [inline]
 [<ffffffff815aca46>] SYSC_symlinkat fs/namei.c:4171 [inline]
 [<ffffffff815aca46>] SyS_symlinkat+0xe6/0x260 fs/namei.c:4158
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9f93>] 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: [<ffffffff8136675c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136675c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425de7>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3769:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f8142>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211ee22>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor3/15373:
 #0:  (sb_writers#17){.+.+.+}, at: [<ffffffff815e0a8f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#17){.+.+.+}, at: [<ffffffff815e0a8f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#22/1){+.+.+.}, at: [<ffffffff815aa01a>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#22/1){+.+.+.}, at: [<ffffffff815aa01a>] filename_create+0x17a/0x490 fs/namei.c:3639
2 locks held by syz-executor3/15400:
 #0:  (sb_writers#17){.+.+.+}, at: [<ffffffff815e0a8f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#17){.+.+.+}, at: [<ffffffff815e0a8f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#22/1){+.+.+.}, at: [<ffffffff815aa01a>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#22/1){+.+.+.}, at: [<ffffffff815aa01a>] filename_create+0x17a/0x490 fs/namei.c:3639

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

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.113-g47bbcd6 #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8607d08 ffffffff81eb32a9 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b9bd0 ffff8801d8607d40
 ffffffff81ebe5a7 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb32a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb32a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebe5a7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebe53a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366cf4>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366cf4>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366cf4>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366cf4>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fa15c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff839f8ba6