INFO: task syz-executor:8459 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:21512 pid:8459  tgid:8459  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: 0033:0x7f4a8558ff17
RSP: 002b:00007ffd99a545f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4a85611c05 RCX: 00007f4a8558ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd99a546b0
RBP: 00007ffd99a546b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd99a55740
R13: 00007f4a85611c05 R14: 000000000001b99e R15: 00007ffd99a55780
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 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+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: 19157 Comm: syz.9.1236 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_in+0x3a/0xc0
Code: 49 bc 00 00 00 00 00 fc ff df e8 e1 8c 70 fc 4d 8d be f9 00 00 00 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 75 51 45 0f b6 3f <bf> 20 00 00 00 44 89 fe e8 b9 8f 70 fc 41 83 ff 1f 77 4e e8 ae 8c
RSP: 0000:ffffc90009d46cf8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88803cad9cc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff99def3a0
RBP: ffffc90009d46ed0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff854f1e30 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff99def3a0 R15: 0000000000000000
FS:  00007f18e0dd56c0(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f801c5704d3 CR3: 0000000120ce8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 serial8250_console_write+0x584/0x1ba0
 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_noprof+0xb2/0xf0
 nilfs_ioctl+0x1d66/0x24d0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f18e2b8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f18e0dd5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f18e2db6090 RCX: 00007f18e2b8ebe9
RDX: 0000200000000040 RSI: 0000000040186e8d RDI: 0000000000000004
RBP: 00007f18e2c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f18e2db6128 R14: 00007f18e2db6090 R15: 00007ffc988d8a38
 </TASK>
