INFO: task syz.1.1835:12699 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1835      state:D stack:25128 pid:12699 tgid:12698 ppid:5874   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 sync_bdevs+0x1ac/0x340
 ksys_sync+0xb9/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe244b8ec29
RSP: 002b:00007fe245991038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe244dd5fa0 RCX: 00007fe244b8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe244dd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe244dd6038 R14: 00007fe244dd5fa0 R15: 00007ffe85cd8238
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by syslogd/5278:
 #0: ffff88813663a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff888136624048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
2 locks held by udevd/5296:
2 locks held by getty/5680:
 #0: ffff888025ea00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000290e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by udevd/5878:
 #0: ffff888022774358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.1.1835/12699:
 #0: ffff888022774358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
2 locks held by syz.2.2612/15985:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 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+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11669 Comm: ipvs-e:9:0 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
RIP: 0010:ip_vs_estimation_kthread+0x16e4/0x3a00
Code: 00 00 00 74 0a e8 4c c0 cd f7 e9 88 11 00 00 48 8b 84 24 98 00 00 00 42 80 3c 38 00 74 08 4c 89 f7 e8 d0 61 33 f8 49 83 3e 00 <0f> 84 56 10 00 00 48 c7 c7 c0 6c 7f 8f 31 f6 e8 b8 70 8e 01 c7 84
RSP: 0018:ffffc9000ae6fac0 EFLAGS: 00000246
RAX: 1ffff11005286930 RBX: 0000000000000026 RCX: 0000000000000000
RDX: ffff888108f3d700 RSI: 0000000000000026 RDI: ffff88803021c9a8
RBP: ffffc9000ae6fd70 R08: ffffffff8fc35777 R09: 1ffffffff1f86aee
R10: dffffc0000000000 R11: fffffbfff1f86aef R12: 0000000000000003
R13: 1ffff110211e7dd9 R14: ffff888029434980 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881a39fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc1015ff000 CR3: 00000001107c4000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
