IPVS: length: 193 != 8
IPVS: length: 193 != 8
INFO: task syz-executor0:3720 blocked for more than 140 seconds.
      Not tainted 4.9.124-g09eb2ba #31
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D27240  3720      1 0x00000004
 ffff8801c412e000 ffff8801c5df6a00 ffff8801c5a6df80 ffff8801c5214800
 ffff8801db321c18 ffff8801a13d7b40 ffffffff839f0afd 0000000000000002
 0000000041b58ab3 ffffffff843bbc94 00ffffff81223870 ffff8801db3224e8
Call Trace:
 [<ffffffff839f20ff>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff816073d9>] wb_wait_for_completion+0x149/0x1b0 fs/fs-writeback.c:221
 [<ffffffff81607647>] __writeback_inodes_sb_nr+0x207/0x300 fs/fs-writeback.c:2310
 [<ffffffff81607797>] writeback_inodes_sb_nr fs/fs-writeback.c:2327 [inline]
 [<ffffffff81607797>] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2342
 [<ffffffff8161f353>] __sync_filesystem fs/sync.c:35 [inline]
 [<ffffffff8161f353>] sync_filesystem+0x93/0x240 fs/sync.c:63
 [<ffffffff8157ddc5>] generic_shutdown_super+0x75/0x300 fs/super.c:423
 [<ffffffff8157e6ff>] kill_block_super+0x9f/0x120 fs/super.c:1127
 [<ffffffff8157ea75>] deactivate_locked_super+0x75/0xd0 fs/super.c:310
 [<ffffffff8157f481>] deactivate_super+0x91/0xd0 fs/super.c:341
 [<ffffffff815e1692>] cleanup_mnt+0xb2/0x160 fs/namespace.c:1143
 [<ffffffff815e17c6>] __cleanup_mnt+0x16/0x20 fs/namespace.c:1150
 [<ffffffff8119a66c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff8100559c>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100559c>] exit_to_usermode_loop+0xfc/0x120 arch/x86/entry/common.c:161
 [<ffffffff810064d4>] prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 [<ffffffff810064d4>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff810064d4>] do_syscall_64+0x364/0x490 arch/x86/entry/common.c:287
 [<ffffffff83a019d3>] 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: [<ffffffff813689dc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813689dc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81428248>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3624:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839ffba2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82125402>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor0/3720:
 #0:  (&type->s_umount_key#40){+.+...}, at: [<ffffffff8157f479>] deactivate_super+0x89/0xd0 fs/super.c:340

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8787d08 ffffffff81eb95e9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d8787d40
 ffffffff81ec4927 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb95e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb95e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec4927>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec48ba>] 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
 [<ffffffff81368f74>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81368f74>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368f74>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368f74>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01b9c>] 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: 114 Comm: kworker/u4:2 Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn
c (flush-7:0)
c
task: ffff8801d9688000 task.stack: ffff8801d9760000
RIP: 0010:[<ffffffff81232d3d>] 
c [<ffffffff81232d3d>] lock_is_held+0xdd/0x140 kernel/locking/lockdep.c:3795
RSP: 0018:ffff8801d9767610  EFLAGS: 00000807
RAX: dffffc0000000000 RBX: 0000000000000246 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff846df4a0 RDI: ffff8801d96888c4
RBP: ffff8801d9767628 R08: ffff8801d9688960 R09: 0000000000000001
R10: ffff8801d9688000 R11: 1ffff1003b2d1127 R12: ffff8801d9688000
R13: 0000000000000001 R14: 0000000002420848 R15: ffff8801d9c17688
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff243ef5000 CR3: 00000001c7b23000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffea0006c84e00
c ffff8801c9ae5628
c dffffc0000000000
c ffff8801d9767638
c
 ffffffff8127e464
c ffff8801d97676a0
c ffffffff8143b3db
c ffffffff8143b090
c
 ffffffff816288d3
c ffff8801d9c17554
c 0000000000000000
c ffff8801d9c17690
c
Call Trace:
 [<ffffffff8127e464>] rcu_read_lock_held+0xa4/0xc0 kernel/rcu/update.c:297
 [<ffffffff8143b3db>] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline]
 [<ffffffff8143b3db>] find_get_entry+0x34b/0x540 mm/filemap.c:1095
 [<ffffffff8143c50b>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1201
 [<ffffffff81629ba9>] find_or_create_page include/linux/pagemap.h:309 [inline]
 [<ffffffff81629ba9>] grow_dev_page fs/buffer.c:1005 [inline]
 [<ffffffff81629ba9>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81629ba9>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81629ba9>] __getblk_gfp+0x249/0x710 fs/buffer.c:1386
 [<ffffffff8162d48d>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818db771>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818db771>] fat_clusters_flush+0x111/0x380 fs/fat/misc.c:69
 [<ffffffff818d56d2>] fat_write_inode+0xf2/0x170 fs/fat/inode.c:898
 [<ffffffff81606add>] write_inode fs/fs-writeback.c:1180 [inline]
 [<ffffffff81606add>] __writeback_single_inode+0x86d/0x1020 fs/fs-writeback.c:1379
 [<ffffffff81607ddc>] writeback_sb_inodes+0x4ac/0xe70 fs/fs-writeback.c:1584
 [<ffffffff81608ddf>] wb_writeback+0x2cf/0xbd0 fs/fs-writeback.c:1760
 [<ffffffff8161230e>] wb_do_writeback fs/fs-writeback.c:1894 [inline]
 [<ffffffff8161230e>] wb_workfn+0x20e/0xdb0 fs/fs-writeback.c:1930
 [<ffffffff8118f461>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff81190256>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01b9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Code: 
cff 
cff 
c65 
c4c 
c8b 
c24 
c25 
cc0 
c7d 
c01 
c00 
c49 
c8d 
cbc 
c24 
cc4 
c08 
c00 
c00 
c41 
c89 
cc5 
c48 
cb8 
c00 
c00 
c00 
c00 
c00 
cfc 
cff 
cdf 
c48 
c89 
cfa 
c48 
cc1 
cea 
c03 
c0f 
cb6 
c14 
c02 
c<48> 
c89 
cf8 
c83 
ce0 
c07 
c83 
cc0 
c03 
c38 
cd0 
c7c 
c04 
c84 
cd2 
c75 
c3a 
c41 
cc7 
c84 
c24 
c