INFO: task syz-executor:5872 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc7-syzkaller-g5f33ebd2018c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21784 pid:5872  tgid:5872  ppid:1      task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148
 __flush_work+0x9b9/0xbc0 kernel/workqueue.c:4246
 flush_work kernel/workqueue.c:4267 [inline]
 flush_delayed_work+0x13e/0x190 kernel/workqueue.c:4289
 invalidate_dquots fs/quota/dquot.c:576 [inline]
 dquot_disable+0x762/0x1bc0 fs/quota/dquot.c:2296
 ocfs2_disable_quotas+0xfa/0x220 fs/ocfs2/super.c:967
 ocfs2_dismount_volume+0x1ba/0x8d0 fs/ocfs2/super.c:1818
 generic_shutdown_super+0x132/0x2c0 fs/super.c:643
 kill_block_super+0x44/0x90 fs/super.c:1755
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f96c3b8fc97
RSP: 002b:00007ffd30e20768 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f96c3c1089d RCX: 00007f96c3b8fc97
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd30e20820
RBP: 00007ffd30e20820 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd30e218b0
R13: 00007f96c3c1089d R14: 0000000000049747 R15: 00007ffd30e218f0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/26:
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/u4:7/1040:
2 locks held by getty/5128:
 #0: ffff8880006990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000018e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by kworker/0:5/5464:
2 locks held by kworker/0:6/5465:
1 lock held by syz-executor/5872:
 #0: ffff888040b480e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff888040b480e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff888040b480e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
1 lock held by syz.5.449/7745:
1 lock held by syz.3.450/7747:
1 lock held by syz.2.452/7751:
3 locks held by syz.4.453/7754:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 26 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller-g5f33ebd2018c #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>