INFO: task syz-executor4:12764 blocked for more than 120 seconds.
      Not tainted 4.4.120-gd63fdf6 #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D ffff8801d2d5f520 27336 12764   3848 0x20020004
 ffff8801d2d5f520 ffff8800aa5e0838 ffffe8ffffc13c00 ffff8800aa5e0830
 ffff8801d2d5f4f8 ffff8801d2d5f500 ffff8801db21fdb8 ffff8801db21fde0
 ffff8801db21f4d8 ffff8801cabcb000 ffff8801c12a0000 0000000000000000
Call Trace:
 [<ffffffff8376582a>] schedule+0x7a/0x1b0 kernel/sched/core.c:3353
 [<ffffffff83770b40>] schedule_timeout+0x3a0/0x970 kernel/time/timer.c:1515
 [<ffffffff837637be>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:4935
 [<ffffffff815ddcbd>] io_schedule include/linux/sched.h:447 [inline]
 [<ffffffff815ddcbd>] dio_await_one fs/direct-io.c:449 [inline]
 [<ffffffff815ddcbd>] dio_await_completion fs/direct-io.c:503 [inline]
 [<ffffffff815ddcbd>] do_blockdev_direct_IO+0x476d/0x8810 fs/direct-io.c:1313
 [<ffffffff815e1e0e>] __blockdev_direct_IO+0xae/0xe0 fs/direct-io.c:1342
 [<ffffffff815d0b42>] blkdev_direct_IO+0xb2/0xe0 fs/block_dev.c:167
 [<ffffffff81423c50>] generic_file_read_iter+0x360/0x1160 mm/filemap.c:1791
 [<ffffffff815d1ba5>] blkdev_read_iter+0x105/0x170 fs/block_dev.c:1679
 [<ffffffff8151d169>] new_sync_read fs/read_write.c:422 [inline]
 [<ffffffff8151d169>] __vfs_read+0x339/0x440 fs/read_write.c:434
 [<ffffffff8151edd3>] vfs_read+0x123/0x3a0 fs/read_write.c:454
 [<ffffffff81521adf>] SYSC_pread64 fs/read_write.c:607 [inline]
 [<ffffffff81521adf>] SyS_pread64+0x13f/0x170 fs/read_write.c:594
 [<ffffffff81119c69>] sys32_pread+0x39/0x50 arch/x86/ia32/sys_ia32.c:179
 [<ffffffff81006d91>] do_syscall_32_irqs_on arch/x86/entry/common.c:392 [inline]
 [<ffffffff81006d91>] do_fast_syscall_32+0x321/0x8a0 arch/x86/entry/common.c:459
 [<ffffffff837752ea>] sysenter_flags_fixed+0xd/0x17
no locks held by syz-executor4/12764.
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 485 Comm: khungtaskd Not tainted 4.4.120-gd63fdf6 #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800bac7e000 task.stack: ffff8800bac80000
RIP: 0010:[<ffffffff810c3e67>]  [<ffffffff810c3e67>] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline]
RIP: 0010:[<ffffffff810c3e67>]  [<ffffffff810c3e67>] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline]
RIP: 0010:[<ffffffff810c3e67>]  [<ffffffff810c3e67>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline]
RIP: 0010:[<ffffffff810c3e67>]  [<ffffffff810c3e67>] flat_send_IPI_mask+0xf7/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8800bac87cb8  EFLAGS: 00000046
RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300
RBP: ffff8800bac87ce0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246
R13: 0000000000000003 R14: ffffffff8426f420 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f623b2569b8 CR3: 00000001d3ec6000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8426f420 ffffffff847efb00 fffffbfff08fda14 dffffc0000000000
 ffff8801db31bca0 ffff8800bac87d00 ffffffff810b999b ffffffff839f63c0
 0000000000000003 ffff8800bac87d60 ffffffff81d0eff4 0000000000000000
Call Trace:
 [<ffffffff810b999b>] nmi_raise_cpu_backtrace+0x5b/0x70 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81d0eff4>] nmi_trigger_all_cpu_backtrace+0x4a4/0x550 lib/nmi_backtrace.c:85
 [<ffffffff810b9a34>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff81368c9a>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff81368c9a>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368c9a>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368c9a>] watchdog+0x6fa/0xae0 kernel/hung_task.c:238
 [<ffffffff81190788>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff83773d85>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:506
Code: b3 5f ff f6 c4 10 75 e1 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 74 1a e8 6b 2f 17 00 4c 89 e7 57 9d 0f 1f 
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.120-gd63fdf6 #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d9b49800 task.stack: ffff8801d9b58000
RIP: 0010:[<ffffffff810c341c>]  [<ffffffff810c341c>] native_apic_mem_write+0xc/0x10 arch/x86/include/asm/apic.h:94
RSP: 0018:ffff8801d9b5fc08  EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff8426f420 RCX: 0000000000000020
RDX: 1ffffffff084dea1 RSI: 000000000a71d304 RDI: 0000000000000380
RBP: ffff8801d9b5fc08 R08: ffff88021fffd058 R09: 0000000000000004
R10: ffffed0043fffa09 R11: 0000000000000000 R12: 000000000a71d304
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76dc2e6000 CR3: 00000001d3ec6000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d9b5fc28 ffffffff810b07fa 0000000000000000 ffff8801db317fc0
 ffff8801d9b5fc68 ffffffff812cfdda 00000038d2e7681f ffff8801db317fc0
 0000000000000001 ffff8801db319640 0000000000000001 0000000000000000
Call Trace:
 [<ffffffff810b07fa>] apic_write arch/x86/include/asm/apic.h:392 [inline]
 [<ffffffff810b07fa>] lapic_next_event+0x5a/0x90 arch/x86/kernel/apic/apic.c:458
 [<ffffffff812cfdda>] clockevents_program_event+0x28a/0x350 kernel/time/clockevents.c:339
 [<ffffffff812d4c68>] tick_program_event+0xa8/0x110 kernel/time/tick-oneshot.c:47
 [<ffffffff812ac6e6>] hrtimer_force_reprogram kernel/time/hrtimer.c:601 [inline]
 [<ffffffff812ac6e6>] __remove_hrtimer+0x1f6/0x250 kernel/time/hrtimer.c:929
 [<ffffffff812ad153>] remove_hrtimer kernel/time/hrtimer.c:958 [inline]
 [<ffffffff812ad153>] hrtimer_try_to_cancel+0x2b3/0x660 kernel/time/hrtimer.c:1059
 [<ffffffff812ad522>] hrtimer_cancel+0x22/0x40 kernel/time/hrtimer.c:1079
 [<ffffffff812d581e>] tick_nohz_restart+0x1e/0x190 kernel/time/tick-sched.c:559
 [<ffffffff812d7877>] tick_nohz_restart_sched_tick kernel/time/tick-sched.c:726 [inline]
 [<ffffffff812d7877>] tick_nohz_idle_exit+0x247/0x3d0 kernel/time/tick-sched.c:946
 [<ffffffff81221815>] cpu_idle_loop kernel/sched/idle.c:267 [inline]
 [<ffffffff81221815>] cpu_startup_entry+0x2a5/0x8f0 kernel/sched/idle.c:301
 [<ffffffff810adc64>] start_secondary+0x304/0x3e0 arch/x86/kernel/smpboot.c:242
Code: a0 06 00 66 90 66 2e 0f 1f 84 00 00 00 00 00 55 be 01 00 00 00 48 89 e5 e8 e2 d1 1b 00 5d c3 55 89 ff 48 89 e5 89 b7 00 b0 5f ff <5d> c3 66 90 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 89 fb