INFO: task syz.3.5156:29507 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.5156      state:D stack:25256 pid:29507 tgid:29506 ppid:28400  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 sync_inodes_sb+0x1bb/0xa10
 __iterate_supers+0x13d/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5c0b78ebe9
RSP: 002b:00007f5c0c643038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f5c0b9b5fa0 RCX: 00007f5c0b78ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f5c0b9b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5c0b9b6038 R14: 00007f5c0b9b5fa0 R15: 00007ffdb3b25918
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: bat_events batadv_nc_worker
RIP: 0010:batadv_nc_worker+0xf8/0x610
Code: 00 00 00 00 48 c7 c7 a0 9e 13 8e 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 55 e8 31 56 56 f6 48 83 c4 08 e8 a8 7a 32 00 <89> c3 31 ff 89 c6 e8 2d ab 78 f6 85 db 74 10 e8 d4 58 5f f6 84 c0
RSP: 0018:ffffc90000107a20 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888110e95800 RCX: 8945ae2e16e1bf00
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: ffff888109e39570 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8b470340 R12: dffffc0000000000
R13: ffffffff8b470412 R14: ffff888120434d80 R15: 00000000000002ae
FS:  0000000000000000(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555577bd55c8 CR3: 000000010db52000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
