Buffer I/O error on dev loop0, logical block 0, async page read
INFO: task syz-executor1:9811 blocked for more than 120 seconds.
      Not tainted 4.9.92-g4fb542f #2
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor1   D28584  9811   3838 0x20020004
 ffff8801d9240000 ffff8801cd38df80 ffff8801a1684540 ffff8801cd788000
 ffff8801db221b98 ffff8801d4ff73d0 ffffffff838c49cd 0000000041b58ab3
 ffffffff841a4570 ffffffff81233c60 0000000000000000 ffff8801db222468
Call Trace:
 [<ffffffff838c5fcf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3556
 [<ffffffff838d23e1>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff838c41aa>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5178
 [<ffffffff838c7419>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838c7419>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838c6cbe>] __wait_on_bit_lock+0xce/0x1c0 kernel/sched/wait.c:421
 [<ffffffff8143267f>] __lock_page+0xff/0x160 mm/filemap.c:934
 [<ffffffff8146853b>] lock_page include/linux/pagemap.h:454 [inline]
 [<ffffffff8146853b>] invalidate_inode_pages2_range+0x41b/0xa10 mm/truncate.c:614
 [<ffffffff8143b40a>] generic_file_direct_write+0x3fa/0x510 mm/filemap.c:2629
 [<ffffffff8143b73f>] __generic_file_write_iter+0x21f/0x540 mm/filemap.c:2823
 [<ffffffff81630ec7>] blkdev_write_iter+0x1b7/0x370 fs/block_dev.c:1718
 [<ffffffff8156e6a4>] do_iter_readv_writev+0x3d4/0x4b0 fs/read_write.c:695
 [<ffffffff81571d48>] compat_do_readv_writev+0x2f8/0x7a0 fs/read_write.c:1089
 [<ffffffff81572775>] compat_writev+0xe5/0x150 fs/read_write.c:1227
 [<ffffffff815728d2>] do_compat_writev+0xf2/0x1d0 fs/read_write.c:1247
 [<ffffffff81574d06>] C_SYSC_writev fs/read_write.c:1258 [inline]
 [<ffffffff81574d06>] compat_SyS_writev+0x26/0x30 fs/read_write.c:1254
 [<ffffffff81006da7>] do_syscall_32_irqs_on arch/x86/entry/common.c:325 [inline]
 [<ffffffff81006da7>] do_fast_syscall_32+0x2f7/0x870 arch/x86/entry/common.c:387
 [<ffffffff838d6fd0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

Showing all locks held in the system:
2 locks held by khungtaskd/515:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643ec>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643ec>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423dc0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3649:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d582c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3745:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838d3a72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff820080d2>] n_tty_read+0x202/0x16b0 drivers/tty/n_tty.c:2133
1 lock held by blkid/7618:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162e23b>] __blkdev_put+0xbb/0x840 fs/block_dev.c:1579

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

NMI backtrace for cpu 1
CPU: 1 PID: 515 Comm: khungtaskd Not tainted 4.9.92-g4fb542f #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d879fd08 ffffffff81d9c509 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b7d90 ffff8801d879fd40
 ffffffff81da7847 0000000000000001 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81d9c509>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d9c509>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81da7847>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81da77da>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7e94>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364984>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364984>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364984>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364984>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ab0d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838d5a9c>] 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: 0 Comm: swapper/0 Not tainted 4.9.92-g4fb542f #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffffffff84429880 task.stack: ffffffff84400000
RIP: 0010:[<ffffffff811fc97d>] 
c [<ffffffff811fc97d>] update_sd_lb_stats+0x101d/0x3a20 kernel/sched/fair.c:8924
RSP: 0018:ffff8801db207900  EFLAGS: 00000246
RAX: ffff8801d9acd410 RBX: ffff8801d9acd400 RCX: ffff8801db207b08
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801d9acd410
RBP: ffff8801db207a98 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8801db207b98 R11: 0000000000000001 R12: 000000000000024d
R13: 0000000000000000 R14: ffff8801db207bb8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f5725db0 CR3: 00000001ce1ee000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff81279c13
c ffff8801db221c20
c ffff8801db2079c0
c ffffffff84429880
c
 1ffff1003b640f39
c 1ffff1003b640f3a
c 00000000844dede0
c 00000000db207b18
c
 ffff8801db207b20
c ffff8801db207b18
c ffff8801db207d28
c fffffbfff0881200
c
Call Trace:
 [<ffffffff811ff410>] find_busiest_group+0x90/0x12e0 kernel/sched/fair.c:9186
 [<ffffffff81200a00>] load_balance+0x3a0/0x2fa0 kernel/sched/fair.c:9472
 [<ffffffff81205aee>] rebalance_domains+0x6be/0xbc0 kernel/sched/fair.c:10113
 [<ffffffff812062e9>] run_rebalance_domains+0x2f9/0x510 kernel/sched/fair.c:10331
 [<ffffffff838dc4bb>] __do_softirq+0x20b/0x937 kernel/softirq.c:284
 [<ffffffff81148dc7>] invoke_softirq kernel/softirq.c:364 [inline]
 [<ffffffff81148dc7>] irq_exit+0x147/0x190 kernel/softirq.c:405
 [<ffffffff838da061>] smp_reschedule_interrupt+0x71/0x90 arch/x86/kernel/smp.c:270
 [<ffffffff838d7bd0>] reschedule_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:671
 <EOI> 
d [<ffffffff838d44d6>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53
 [<ffffffff838d3b15>] arch_safe_halt arch/x86/include/asm/paravirt.h:104 [inline]
 [<ffffffff838d3b15>] default_idle+0x55/0x360 arch/x86/kernel/process.c:295
 [<ffffffff81069fa0>] arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:286
 [<ffffffff838d4935>] default_idle_call+0x45/0x60 kernel/sched/idle.c:97
 [<ffffffff81220725>] cpuidle_idle_call kernel/sched/idle.c:155 [inline]
 [<ffffffff81220725>] cpu_idle_loop kernel/sched/idle.c:248 [inline]
 [<ffffffff81220725>] cpu_startup_entry+0x2b5/0x380 kernel/sched/idle.c:303
 [<ffffffff838c179c>] rest_init+0x183/0x189 init/main.c:408
 [<ffffffff84a73943>] start_kernel+0x67e/0x6b2 init/main.c:663
 [<ffffffff84a7229a>] x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:196
 [<ffffffff84a723db>] x86_64_start_kernel+0x13f/0x162 arch/x86/kernel/head64.c:177
Code: 
c30 
cff 
cff 
cff 
c48 
c8b 
c85 
c28 
cff 
cff 
cff 
c48 
cc1 
ce8 
c03 
c42 
c80 
c3c 
c38 
c00 
c0f 
c85 
c8c 
c13 
c00 
c00 
c48 
c8b 
c85 
c28 
cff 
cff 
cff 
c48 
c8b 
c18 
c48 
c8d 
c7b 
c10 
c48 
c89 
cf8 
c<48> 
cc1 
ce8 
c03 
c42 
c80 
c3c 
c38 
c00 
c0f 
c85 
c8b 
c13 
c00 
c00 
c48 
c8b 
c85 
c30 
cff 
cff 
c