INFO: task syz-executor:5774 blocked for more than 152 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21320 pid:5774  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
 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+0x2c6/0x5a0 kernel/sched/completion.c:148
 __flush_work+0x92f/0xac0 kernel/workqueue.c:3475
 flush_work kernel/workqueue.c:3496 [inline]
 flush_delayed_work+0x131/0x180 kernel/workqueue.c:3620
 dquot_writeback_dquots+0x101/0x860 fs/quota/dquot.c:719
 jfs_sync_fs+0x73/0xa0 fs/jfs/super.c:683
 sync_filesystem+0xea/0x220 fs/sync.c:56
 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
 kill_block_super+0x44/0x90 fs/super.c:1668
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:180
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213
 __syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8d97b9f397
RSP: 002b:00007ffe0261ab58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f8d97c344bb RCX: 00007f8d97b9f397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe0261ac10
RBP: 00007ffe0261ac10 R08: 00007ffe0261bc10 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe0261bca0
R13: 00007f8d97c344bb R14: 000000000001f571 R15: 00007ffe0261bce0
 </TASK>
INFO: task syz-executor:5777 blocked for more than 154 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21160 pid:5777  ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
 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+0x2c6/0x5a0 kernel/sched/completion.c:148
 __flush_work+0x92f/0xac0 kernel/workqueue.c:3475
 flush_work kernel/workqueue.c:3496 [inline]
 flush_delayed_work+0x131/0x180 kernel/workqueue.c:3620
 invalidate_dquots fs/quota/dquot.c:605 [inline]
 dquot_disable+0x723/0x1bc0 fs/quota/dquot.c:2331
 ocfs2_disable_quotas+0xfa/0x210 fs/ocfs2/super.c:963
 ocfs2_dismount_volume+0x19e/0x890 fs/ocfs2/super.c:1874
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1668
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:180
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213
 __syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7d4959f397
RSP: 002b:00007ffe89a4bd18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f7d496344bb RCX: 00007f7d4959f397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe89a4bdd0
RBP: 00007ffe89a4bdd0 R08: 00007ffe89a4cdd0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe89a4ce60
R13: 00007f7d496344bb R14: 000000000001e1c9 R15: 00007ffe89a4cea0
 </TASK>
INFO: task syz-executor:5778 blocked for more than 155 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:20616 pid:5778  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
 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+0x2c6/0x5a0 kernel/sched/completion.c:148
 __flush_work+0x92f/0xac0 kernel/workqueue.c:3475
 flush_work kernel/workqueue.c:3496 [inline]
 flush_delayed_work+0x131/0x180 kernel/workqueue.c:3620
 invalidate_dquots fs/quota/dquot.c:605 [inline]
 dquot_disable+0x723/0x1bc0 fs/quota/dquot.c:2331
 ocfs2_disable_quotas+0xfa/0x210 fs/ocfs2/super.c:963
 ocfs2_dismount_volume+0x19e/0x890 fs/ocfs2/super.c:1874
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1668
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:180
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213
 __syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3ca8d9f397
RSP: 002b:00007ffe169fc398 EFLAGS: 00000246
 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3ca8e344bb RCX: 00007f3ca8d9f397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe169fc450
RBP: 00007ffe169fc450 R08: 00007ffe169fd450 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe169fd4e0
R13: 00007f3ca8e344bb R14: 0000000000021360 R15: 00007ffe169fd520
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6635
3 locks held by kworker/u4:6/1105:
 #0: ffff88814c224938 ((wq_completion)ipv6_addrconf
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc900043bfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc900043bfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #2: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xce/0x1550 net/ipv6/addrconf.c:4188
12 locks held by kworker/u4:7/1123:
3 locks held by kworker/u4:9/3456:
2 locks held by getty/5530:
 #0: ffff888031de10a0 (&tty->ldisc_sem){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
1 lock held by syz-executor/5774:
 #0: ffff88807f7b60e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88807f7b60e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88807f7b60e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/5777:
 #0: ffff888025a1e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff888025a1e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff888025a1e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/5778:
 #0: ffff8880265160e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880265160e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880265160e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/5779:
 #0: ffff888045c6a0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff888045c6a0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff888045c6a0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/6758:
 #0: ffff88807955c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88807955c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88807955c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/6884:
 #0: 
ffff88802e4fe0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
ffff88802e4fe0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
ffff88802e4fe0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
3 locks held by kworker/u4:10/6907:
 #0: ffff888017c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #0: ffff888017c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc90019617d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc90019617d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #2: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
1 lock held by syz-executor/7092:
 #0: ffff8880450ea0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880450ea0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880450ea0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/7300:
 #0: ffff88807840e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88807840e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88807840e0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
1 lock held by syz-executor/7695:
 #0: ffffffff8e3d0988 (
rtnl_mutex
){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
, at: rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6481
1 lock held by syz-executor/7699:
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6481
1 lock held by syz-executor/7728:
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6481
5 locks held by syz-executor/7737:

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf59/0xfa0 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1123 Comm: kworker/u4:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: quota_events_unbound quota_release_workfn
RIP: 0010:io_serial_in+0x77/0xb0 drivers/tty/serial/8250/8250_port.c:417
Code: e8 0e 98 d4 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 0f 24 2d fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 44 89 f9 80 e1 07 38 c1 7c aa 4c
RSP: 0018:ffffc9000460eaf8 EFLAGS: 00000002
RAX: 1ffffffff2ec4a00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc9000460ecd0 R08: ffff888020e00237 R09: 1ffff110041c0046
R10: dffffc0000000000 R11: ffffed10041c0047 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff97625440 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005629f88af168 CR3: 000000000cf32000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:117 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:139 [inline]
 wait_for_lsr drivers/tty/serial/8250/8250_port.c:2084 [inline]
 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3373 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3395 [inline]
 serial8250_console_write+0xff9/0x18b0 drivers/tty/serial/8250/8250_port.c:3480
 console_emit_next_record kernel/printk/printk.c:2944 [inline]
 console_flush_all+0x6ad/0xcf0 kernel/printk/printk.c:3000
 console_unlock+0xad/0x350 kernel/printk/printk.c:3069
 vprintk_emit+0x497/0x610 kernel/printk/printk.c:2341
 _printk+0xde/0x130 kernel/printk/printk.c:2366
 __mlog_printk+0x280/0x2b0 fs/ocfs2/cluster/masklog.c:77
 ocfs2_block_check_validate+0x2ec/0x630 fs/ocfs2/blockcheck.c:400
 ocfs2_read_blocks+0xf44/0x1450 fs/ocfs2/buffer_head_io.c:380
 ocfs2_read_quota_phys_block fs/ocfs2/quota_global.c:157 [inline]
 ocfs2_quota_read+0x2ea/0x960 fs/ocfs2/quota_global.c:199
 __ocfs2_sync_dquot+0x22b/0x10b0 fs/ocfs2/quota_global.c:494
 ocfs2_global_release_dquot fs/ocfs2/quota.h:108 [inline]
 ocfs2_release_dquot+0x572/0xb60 fs/ocfs2/quota_global.c:762
 quota_release_workfn+0x365/0x5e0 fs/quota/dquot.c:874
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>