buffer_io_error: 5 callbacks suppressed
Buffer I/O error on dev loop0, logical block 33008, async page read
INFO: task syz-executor5:10800 blocked for more than 120 seconds.
      Not tainted 4.4.128-gbd23e3a #19
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D ffff8801ccef79e8 26800 10800   3863 0x20020006
 ffff8801ccef79e8 0000000000000000 ffff8800b2f2d0e0 ffffed00165e5a1b
 ffff8800b2f2c800 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8
 ffff8801db21f4c0 ffffffff84417840 ffff8800b2f2c800 0000000000000000
Call Trace:
 [<ffffffff838b074a>] schedule+0x7a/0x1b0 kernel/sched/core.c:3359
 [<ffffffff838b0ee3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3392
 [<ffffffff838b7027>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff838b7027>] mutex_lock_nested+0x307/0x850 kernel/locking/mutex.c:621
 [<ffffffff815d280a>] blkdev_put+0x2a/0x560 fs/block_dev.c:1558
 [<ffffffff815d2dcb>] blkdev_close+0x8b/0xb0 fs/block_dev.c:1607
 [<ffffffff81522495>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff815229d5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118bb6f>] task_work_run+0x10f/0x190 kernel/task_work.c:115
 [<ffffffff8115f0e0>] get_signal+0x1190/0x14b0 kernel/signal.c:2147
 [<ffffffff8100e02b>] do_signal+0x8b/0x1d30 arch/x86/kernel/signal.c:712
 [<ffffffff8100360a>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:248
 [<ffffffff81007090>] prepare_exit_to_usermode arch/x86/entry/common.c:283 [inline]
 [<ffffffff81007090>] syscall_return_slowpath arch/x86/entry/common.c:348 [inline]
 [<ffffffff81007090>] do_syscall_32_irqs_on arch/x86/entry/common.c:398 [inline]
 [<ffffffff81007090>] do_fast_syscall_32+0x620/0x8b0 arch/x86/entry/common.c:459
 [<ffffffff838c00aa>] sysenter_flags_fixed+0xd/0x17
1 lock held by syz-executor5/10800:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff815d280a>] blkdev_put+0x2a/0x560 fs/block_dev.c:1558
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 492 Comm: khungtaskd Not tainted 4.4.128-gbd23e3a #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d9120000 task.stack: ffff8801d9330000
RIP: 0010:[<ffffffff810bfd66>]  [<ffffffff810bfd66>] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline]
RIP: 0010:[<ffffffff810bfd66>]  [<ffffffff810bfd66>] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline]
RIP: 0010:[<ffffffff810bfd66>]  [<ffffffff810bfd66>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline]
RIP: 0010:[<ffffffff810bfd66>]  [<ffffffff810bfd66>] flat_send_IPI_mask+0xf6/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8801d9337cc8  EFLAGS: 00000046
RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300
RBP: ffff8801d9337cf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000246
R13: 0000000000000003 R14: 0000000000000002 R15: ffffffff8446f7a0
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000d30000 CR3: 00000000b139c000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8446f7a0 ffffffff84a187a0 0000000000000007 fffffbfff0942ba4
 0000000000000040 ffff8801d9337d10 ffffffff810b5d21 ffffffff83c0b0e0
 0000000000000003 ffff8801d9337d68 ffffffff81e18b43 ffffffff8140da9f
Call Trace:
 [<ffffffff810b5d21>] nmi_raise_cpu_backtrace+0x61/0x80 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81e18b43>] nmi_trigger_all_cpu_backtrace.cold.4+0x70/0xad lib/nmi_backtrace.c:85
 [<ffffffff810b5dc4>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff8141a189>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff8141a189>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8141a189>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8141a189>] watchdog.cold.1+0xd3/0xee kernel/hung_task.c:238
 [<ffffffff81190748>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff838beb95>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:510
Code: b3 5f ff f6 c4 10 75 e2 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 f2 09 da 80 cf 04 41 83 fe 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 75 1a 4c 89 e7 57 9d 0f 1f 44 00 00 e8 82 
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.128-gbd23e3a #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d9b49800 task.stack: ffff8801d9b58000
RIP: 0010:[<ffffffff810cc306>]  [<ffffffff810cc306>] native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:49
RSP: 0018:ffff8801d9b5fda0  EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffffffff84a05868 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801d9b4a0dc
RBP: ffff8801d9b5fda0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: fffffbfff074890c R15: ffffffff84a05868
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f5749c20 CR3: 00000000b139c000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d9b5fdd8 ffffffff81025da5 ffff8801d9b60000 0000000000000000
 0000000000000000 fffffbfff074890c ffffffff84a05868 ffff8801d9b5fde8
 ffffffff810272f0 ffff8801d9b5fe00 ffffffff8121b9c7 dffffc0000000000
Call Trace:
 [<ffffffff81025da5>] arch_safe_halt arch/x86/include/asm/paravirt.h:117 [inline]
 [<ffffffff81025da5>] default_idle+0x55/0x3c0 arch/x86/kernel/process.c:290
 [<ffffffff810272f0>] arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:281
 [<ffffffff8121b9c7>] default_idle_call+0x57/0x70 kernel/sched/idle.c:93
 [<ffffffff8121c16f>] cpuidle_idle_call kernel/sched/idle.c:157 [inline]
 [<ffffffff8121c16f>] cpu_idle_loop kernel/sched/idle.c:253 [inline]
 [<ffffffff8121c16f>] cpu_startup_entry+0x6af/0x780 kernel/sched/idle.c:301
 [<ffffffff810aa174>] start_secondary+0x324/0x400 arch/x86/kernel/smpboot.c:242
Code: 00 00 00 00 00 55 48 89 e5 fa 5d c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 fb 5d c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 fb f4 <5d> c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 f4 5d c3 66 0f 1f 84