INFO: task syz-executor:5849 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21480 pid:5849  tgid:5849  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 v9fs_evict_inode+0x170/0x320
 evict+0x504/0x9c0
 __dentry_kill+0x209/0x660
 dput+0x19f/0x2b0
 shrink_dcache_for_umount+0xa0/0x170
 generic_shutdown_super+0x67/0x2c0
 kill_anon_super+0x3b/0x70
 v9fs_kill_super+0x4c/0x90
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3981f8ff57
RSP: 002b:00007ffdd0c5bff8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3982011c2d RCX: 00007f3981f8ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdd0c5c0b0
RBP: 00007ffdd0c5c0b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdd0c5d140
R13: 00007f3982011c2d R14: 0000000000010e4b R15: 00007ffdd0c5d180
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/0:1/10:
 #0: ffff88801bee1d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900000d7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88802306b198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88802306e518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20
 #4: ffff88802305d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20
 #5: ffffffff8ede16d0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750
5 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5674:
 #0: ffff88801f8850a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by kworker/u8:2/5742:
 #0: ffff88804b039f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff88804b024008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffff88804b025918 (
&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30
1 lock held by syz-executor/5849:
 #0: ffff8880381120e0 (&type->s_umount_key#52){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
1 lock held by syz.6.965/8694:
 #0: ffff8880381120e0 (
&type->s_umount_key
#52
){++++}-{4:4}
, at: super_lock+0x2a9/0x3b0
1 lock held by syz.7.1265/9453:
 #0: 
ffffffff8e13fb78
 (
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: synchronize_rcu_expedited+0x3b9/0x730
5 locks held by syz-executor/9464:

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

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+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 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: 9464 Comm: syz-executor 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:io_serial_out+0x7c/0xc0
Code: ff 6f fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ec 7c d3 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc90008bf72d0 EFLAGS: 00000002
RAX: 0000000000000030 RBX: 0000000000000030 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f8 R08: ffff88801fb68237 R09: 1ffff11003f6d046
R10: dffffc0000000000 R11: ffffffff854fada0 R12: dffffc0000000000
R13: ffffffff99b028c6 R14: ffffffff99df7460 R15: 0000000000000000
FS:  0000555584ee0500(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fce89308710 CR3: 000000003af3a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 serial8250_console_write+0x1410/0x1ba0
 console_flush_all+0x728/0xc40
 console_unlock+0xc4/0x270
 vprintk_emit+0x5b7/0x7a0
 _printk+0xcf/0x120
 hugetlb_show_meminfo_node+0x179/0x320
 __show_mem+0x1f48/0x2190
 warn_alloc+0x2dd/0x310
 __vmalloc_node_range_noprof+0x67e/0x12f0
 vmalloc_user_noprof+0xad/0xf0
 kcov_ioctl+0x55/0x640
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5e39d8e82b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffea905ee30 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f5e39d8e82b
RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d8
RBP: 00007f5e39fd6038 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
