INFO: task syz.5.367:9115 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.367       state:D stack:24608 pid:9115  tgid:9113  ppid:8890   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1585/0x5340
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x899/0x1040
 down_write+0x1bc/0x200
 super_lock+0x289/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1b5b19c799
RSP: 002b:00007f1b5c0ac028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f1b5b415fa0 RCX: 00007f1b5b19c799
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: ffffffff80000201
RBP: 00007f1b5b232bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000080 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1b5b416038 R14: 00007f1b5b415fa0 R15: 00007ffc007dfef8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5628:
 #0: ffff88811403d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by syz-executor/6364:
1 lock held by syz.5.367/9115:
 #0: ffff8881ba35c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x289/0x3d0
1 lock held by syz.1.435/9478:
 #0: ffff8881ba35c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.726/12332:
 #0: ffff8881ba35c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz-executor/12986:
 #0: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
1 lock held by syz.8.915/13579:
1 lock held by syz.8.915/13622:
 #0: ffff8881bb37d5b0 (&inode->i_sb->s_type->i_mutex_dir_key){++++}-{4:4}, at: lookup_slow+0x46/0x70

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 12986 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:asm_sysvec_apic_timer_interrupt+0x0/0x20
Code: 26 07 ad 0a e9 81 06 00 00 90 f3 0f 1e fa 0f 1f 00 fc 6a ff e8 31 05 00 00 48 89 c4 48 89 e7 e8 36 06 ad 0a e9 61 06 00 00 90 <f3> 0f 1e fa 0f 1f 00 fc 6a ff e8 11 05 00 00 48 89 c4 48 89 e7 e8
RSP: 0018:ffffc9000718f958 EFLAGS: 00000093
RAX: ffffffff81a46455 RBX: ffffffff81a462cf RCX: ffff88810e4bd700
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e752720
RBP: ffffc9000718fa30 R08: ffffffff901117b7 R09: 1ffffffff20222f6
R10: dffffc0000000000 R11: fffffbfff20222f7 R12: 0000000000000000
R13: 000000000000005a R14: 0000000000000200 R15: 1ffff92000e31f34
FS:  000055558b2c9500(0000) GS:ffff88818de6d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fb17ff8 CR3: 0000000115a4e000 CR4: 00000000000006f0
Call Trace:
 <TASK>
RIP: 0010:vprintk_emit+0x45d/0x560
Code: 0f 84 44 ff ff ff e8 72 27 21 00 fb eb 44 e8 6a 27 21 00 e8 45 be 08 0a 4d 85 f6 74 94 e8 5b 27 21 00 fb 48 c7 c7 20 27 75 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 16
RSP: 0018:ffffc9000718f980 EFLAGS: 00000293
 _printk+0xdd/0x130
 _btrfs_printk+0x29a/0x320
 btrfs_put_super+0x118/0x1c0
 generic_shutdown_super+0x13d/0x2d0
 kill_anon_super+0x3b/0x70
 btrfs_kill_super+0x41/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f09bb39d9d7
Code: a2 c7 05 1c ed 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffee6f54818 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f09bb431f90 RCX: 00007f09bb39d9d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffee6f548d0
RBP: 00007ffee6f548d0 R08: 00007ffee6f558d0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffee6f55960
R13: 00007f09bb431f90 R14: 000000000004ed6d R15: 00007ffee6f559a0
 </TASK>
