netlink: 4 bytes leftover after parsing attributes in process `syz-executor2'.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor2'.
INFO: task syz-executor3:29443 blocked for more than 120 seconds.
      Not tainted 4.4.135-gb68f27c #52
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D ffff8800ac2afac0 29120 29443   3941 0x20020004
 ffff8800ac2afac0 ffffffff842072e0 ffff8801d9b8b8f8 ffffffff85411340
 ffff8801d9b8b800 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8
 ffff8801db21f4c0 ffff8801d6c63000 ffff8801d9b8b000 0000000000000000
Call Trace:
 [<ffffffff838b474a>] schedule+0x7a/0x1b0 kernel/sched/core.c:3359
 [<ffffffff838bfb61>] schedule_timeout+0x481/0x8b0 kernel/time/timer.c:1515
 [<ffffffff838b788e>] do_wait_for_common kernel/sched/completion.c:75 [inline]
 [<ffffffff838b788e>] __wait_for_common kernel/sched/completion.c:93 [inline]
 [<ffffffff838b788e>] wait_for_common kernel/sched/completion.c:101 [inline]
 [<ffffffff838b788e>] wait_for_completion+0x1fe/0x2e0 kernel/sched/completion.c:122
 [<ffffffff81d5b8f9>] submit_bio_wait+0xf9/0x150 block/bio.c:887
 [<ffffffff81d8df24>] blkdev_issue_flush+0x124/0x1e0 block/blk-flush.c:488
 [<ffffffff815d0815>] blkdev_fsync+0x85/0xb0 fs/block_dev.c:364
 [<ffffffff815bd48c>] vfs_fsync_range+0x10c/0x260 fs/sync.c:195
 [<ffffffff815bd652>] vfs_fsync fs/sync.c:209 [inline]
 [<ffffffff815bd652>] do_fsync+0x42/0xb0 fs/sync.c:219
 [<ffffffff815bddd6>] SYSC_fsync fs/sync.c:228 [inline]
 [<ffffffff815bddd6>] SyS_fsync+0x16/0x20 fs/sync.c:226
 [<ffffffff81006d96>] do_syscall_32_irqs_on arch/x86/entry/common.c:392 [inline]
 [<ffffffff81006d96>] do_fast_syscall_32+0x326/0x8b0 arch/x86/entry/common.c:459
 [<ffffffff838c40aa>] sysenter_flags_fixed+0xd/0x17
no locks held by syz-executor3/29443.
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.135-gb68f27c #52
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffffffff84417840 task.stack: ffffffff84400000
RIP: 0010:[<ffffffff81194236>]  [<ffffffff81194236>] notifier_call_chain+0x186/0x1e0 kernel/notifier.c:83
RSP: 0018:ffffffff84407d80  EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00000000ffffffff
RDX: 0000000000000000 RSI: ffffffff811940d7 RDI: ffffffff8441811c
RBP: ffffffff84407dd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff84417840 R12: 0000000000000002
R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3222aa0140 CR3: 00000001c82e7000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000002 0000000000000000 0000000000000000 0000000000000002
 ffffffff84407db0 ffffffff84483be0 0000000000000002 0000000000000000
 fffffbfff074890c ffffffff84a05f28 ffffffff84407e00 ffffffff8119577f
Call Trace:
 [<ffffffff8119577f>] __atomic_notifier_call_chain kernel/notifier.c:183 [inline]
 [<ffffffff8119577f>] atomic_notifier_call_chain+0x7f/0x140 kernel/notifier.c:193
 [<ffffffff8113058e>] idle_notifier_call_chain+0x1e/0x30 kernel/cpu.c:865
 [<ffffffff8102728f>] __exit_idle arch/x86/kernel/process.c:247 [inline]
 [<ffffffff8102728f>] arch_cpu_idle_exit+0x1f/0x30 arch/x86/kernel/process.c:268
 [<ffffffff8121bf69>] cpu_idle_loop kernel/sched/idle.c:255 [inline]
 [<ffffffff8121bf69>] cpu_startup_entry+0x269/0x780 kernel/sched/idle.c:301
 [<ffffffff838af8b1>] rest_init+0x188/0x18e init/main.c:410
 [<ffffffff84a4b8a1>] start_kernel+0x6b3/0x6e7 init/main.c:682
 [<ffffffff84a4a30f>] x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:196
 [<ffffffff84a4a450>] x86_64_start_kernel+0x13f/0x162 arch/x86/kernel/head64.c:185
Code: 1b 00 48 c7 c2 40 dd a4 83 be 58 00 00 00 48 c7 c7 80 dd a4 83 e8 1b bd f9 ff e8 86 d2 1b 00 4d 85 ed 74 0e e8 7c d2 1b 00 eb 91 <c7> 45 d4 00 00 00 00 e8 6e d2 1b 00 8b 45 d4 48 83 c4 28 5b 41 
NMI backtrace for cpu 1
CPU: 1 PID: 492 Comm: khungtaskd Not tainted 4.4.135-gb68f27c #52
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800bb1a8000 task.stack: ffff8801d90d8000
RIP: 0010:[<ffffffff810bfeb6>]  [<ffffffff810bfeb6>] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline]
RIP: 0010:[<ffffffff810bfeb6>]  [<ffffffff810bfeb6>] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline]
RIP: 0010:[<ffffffff810bfeb6>]  [<ffffffff810bfeb6>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline]
RIP: 0010:[<ffffffff810bfeb6>]  [<ffffffff810bfeb6>] flat_send_IPI_mask+0xf6/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8801d90dfcc8  EFLAGS: 00000046
RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300
RBP: ffff8801d90dfcf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000246
R13: 0000000000000003 R14: 0000000000000002 R15: ffffffff8446f7a0
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c420009e80 CR3: 00000001c82e7000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8446f7a0 ffffffff84a18e60 0000000000000007 fffffbfff0942c7c
 0000000000000040 ffff8801d90dfd10 ffffffff810b5e71 ffffffff83c0b560
 0000000000000003 ffff8801d90dfd68 ffffffff81e19d83 ffff8801d9b8b000
Call Trace:
 [<ffffffff810b5e71>] nmi_raise_cpu_backtrace+0x61/0x80 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81e19d83>] nmi_trigger_all_cpu_backtrace.cold.4+0x70/0xad lib/nmi_backtrace.c:85
 [<ffffffff810b5f14>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff8141a3d9>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff8141a3d9>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8141a3d9>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8141a3d9>] watchdog.cold.1+0xd3/0xee kernel/hung_task.c:238
 [<ffffffff81190958>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff838c2b95>] 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 72