INFO: task syz-executor:25033 blocked for more than 143 seconds.
      Not tainted 5.12.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:12272 pid:25033 ppid:     1 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4322 [inline]
 __schedule+0x2bf/0x7c0 kernel/sched/core.c:5073
 schedule+0x41/0xa0 kernel/sched/core.c:5152
 schedule_timeout+0x100/0x140 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x7f/0xe0 kernel/sched/completion.c:138
 kthread_stop+0x6e/0x170 kernel/kthread.c:621
 ext4_put_super+0x2e6/0x3f0 fs/ext4/super.c:1248
 generic_shutdown_super+0x67/0x100 fs/super.c:464
 kill_block_super+0x1c/0x40 fs/super.c:1394
 deactivate_locked_super+0x2c/0xa0 fs/super.c:335
 cleanup_mnt+0x109/0x150 fs/namespace.c:1136
 task_work_run+0x57/0x90 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x139/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x13/0x40 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f1d672d4227
RSP: 002b:00007ffe2a9ee528 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f1d67345a14 RCX: 00007f1d672d4227
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe2a9ee5e0
RBP: 00007ffe2a9ee5e0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe2a9ef660
R13: 00007f1d67345a14 R14: 00000000000321eb R15: 00007ffe2a9ef6a0
INFO: task kmmpd-loop2:32514 blocked for more than 143 seconds.
      Not tainted 5.12.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kmmpd-loop2     state:D stack:14920 pid:32514 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4322 [inline]
 __schedule+0x2bf/0x7c0 kernel/sched/core.c:5073
 schedule+0x41/0xa0 kernel/sched/core.c:5152
 percpu_rwsem_wait+0x13e/0x180 kernel/locking/percpu-rwsem.c:160
 __percpu_down_read kernel/locking/percpu-rwsem.c:174 [inline]
 __percpu_down_read+0x47/0x50 kernel/locking/percpu-rwsem.c:165
 percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
 __sb_start_write include/linux/fs.h:1640 [inline]
 sb_start_write include/linux/fs.h:1710 [inline]
 write_mmp_block+0x102/0x130 fs/ext4/mmp.c:50
 kmmpd+0x2e0/0x430 fs/ext4/mmp.c:245
 kthread+0x119/0x130 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
2 locks held by kworker/0:2/13:
 #0: ffff888100056738 ((wq_completion)events){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #0: ffff888100056738 ((wq_completion)events){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
 #1: ffffc90000073e70 ((kfence_timer).work){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #1: ffffc90000073e70 ((kfence_timer).work){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
2 locks held by kworker/u4:2/27:
 #0: ffff888100058938 ((wq_completion)events_unbound){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #0: ffff888100058938 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
 #1: ffffc900000efe70 ((work_completion)(&sub_info->work)){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #1: ffffc900000efe70 ((work_completion)(&sub_info->work)){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
1 lock held by khungtaskd/235:
 #0: ffffffff82374a80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0xf2 kernel/locking/lockdep.c:6328
1 lock held by udevd/917:
 #0: ffff888108df80a0 (&bdev->bd_mutex){....}-{3:3}, at: blkdev_get_by_dev fs/block_dev.c:1453 [inline]
 #0: ffff888108df80a0 (&bdev->bd_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x13d/0x250 fs/block_dev.c:1422
2 locks held by getty/977:
 #0: ffff8881057d1898 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x1f/0x50 drivers/tty/tty_ldisc.c:266
 #1: ffffc90001abb2e8 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x478/0x5a0 drivers/tty/n_tty.c:2178
1 lock held by udevd/4901:
 #0: ffff888108df80a0 (&bdev->bd_mutex){....}-{3:3}, at: blkdev_get_by_dev fs/block_dev.c:1453 [inline]
 #0: ffff888108df80a0 (&bdev->bd_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x13d/0x250 fs/block_dev.c:1422
2 locks held by kworker/0:5/11868:
 #0: ffff888100057338 ((wq_completion)rcu_gp){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #0: ffff888100057338 ((wq_completion)rcu_gp){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
 #1: ffffc900024d7e70 ((work_completion)(&rew.rew_work)){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:837 [inline]
 #1: ffffc900024d7e70 ((work_completion)(&rew.rew_work)){....}-{0:0}, at: process_one_work+0x1bc/0x430 kernel/workqueue.c:2238
1 lock held by syz-executor/25033:
 #0: ffff8881155f10e0 (&type->s_umount_key#26){....}-{3:3}, at: deactivate_super+0x27/0x30 fs/super.c:365
1 lock held by kmmpd-loop2/32514:
 #0: ffff8881155f1438 (sb_writers#4){....}-{0:0}, at: kmmpd+0x2e0/0x430 fs/ext4/mmp.c:245
2 locks held by syz.0.19934/21818:
 #0: ffff8881152f30e0 (&type->s_umount_key#22/1){....}-{3:3}, at: alloc_super+0xd0/0x3b0 fs/super.c:229
 #1: ffffffff82375368 (rcu_state.exp_mutex){....}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff82375368 (rcu_state.exp_mutex){....}-{3:3}, at: synchronize_rcu_expedited+0x2f1/0x390 kernel/rcu/tree_exp.h:836
3 locks held by syz.5.19935/21820:
 #0: ffff888100449a90 (&bdev->bd_fsfreeze_mutex){....}-{3:3}, at: freeze_bdev+0x1a/0xc0 fs/block_dev.c:569
 #1: ffff88811583f438 (sb_writers#4){....}-{0:0}, at: sb_wait_write fs/super.c:1592 [inline]
 #1: ffff88811583f438 (sb_writers#4){....}-{0:0}, at: freeze_super+0x73/0x160 fs/super.c:1685
 #2: ffffffff82375368 (rcu_state.exp_mutex){....}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #2: ffffffff82375368 (rcu_state.exp_mutex){....}-{3:3}, at: synchronize_rcu_expedited+0xe6/0x390 kernel/rcu/tree_exp.h:836
2 locks held by syz.4.19936/21827:
 #0: ffff888108dfa4d0 (&bdev->bd_fsfreeze_mutex){....}-{3:3}, at: freeze_bdev+0x1a/0xc0 fs/block_dev.c:569
 #1: ffff888118be9438 (sb_writers#4){....}-{0:0}, at: sb_wait_write fs/super.c:1592 [inline]
 #1: ffff888118be9438 (sb_writers#4){....}-{0:0}, at: freeze_super+0x73/0x160 fs/super.c:1685
2 locks held by syz.1.19938/21834:
 #0: ffff888108df80a0 (&bdev->bd_mutex){....}-{3:3}, at: __blkdev_put+0x4a/0x230 fs/block_dev.c:1574
 #1: ffff888104b7dbf0 (&lo->lo_mutex){....}-{3:3}, at: lo_release+0x1b/0x90 drivers/block/loop.c:1910

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

NMI backtrace for cpu 1
CPU: 1 PID: 235 Comm: khungtaskd Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x69/0x8e lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x32/0x69 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x81/0x90 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0x4b1/0x4c0 kernel/hung_task.c:294
 kthread+0x119/0x130 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13 Comm: kworker/0:2 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events toggle_allocation_gate
RIP: 0010:kmap_local_sched_out kernel/sched/core.c:4092 [inline]
RIP: 0010:prepare_task_switch kernel/sched/core.c:4127 [inline]
RIP: 0010:context_switch kernel/sched/core.c:4274 [inline]
RIP: 0010:__schedule+0x225/0x7c0 kernel/sched/core.c:5073
Code: 00 00 49 0f ba ad 30 13 00 00 00 49 83 bd 20 13 00 00 00 74 06 f0 41 80 4d 00 02 65 48 8b 04 25 c0 6e 01 00 8b 80 e0 13 00 00 <85> c0 0f 85 a9 04 00 00 49 8b b7 38 04 00 00 41 c7 47 34 01 00 00
RSP: 0018:ffffc90000073df8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff82177da8 RCX: 000000000296e009
RDX: 00000052476d74ec RSI: ffff888237c2a918 RDI: ffff888100208928
RBP: ffffc90000073e48 R08: ffff8881075600e8 R09: ffff8881075600e8
R10: 0000000000000016 R11: 0000000000004721 R12: ffff888237c2a900
R13: ffff888100208000 R14: ffff888237c2a918 R15: ffff8881152dcd40
FS:  0000000000000000(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc9e4293000 CR3: 0000000002222000 CR4: 0000000000350ef0
Call Trace:
 preempt_schedule_common kernel/sched/core.c:5233 [inline]
 __cond_resched+0x28/0x40 kernel/sched/core.c:6982
 _cond_resched include/linux/sched.h:1893 [inline]
 process_one_work+0x2c2/0x430 kernel/workqueue.c:2301
 worker_thread+0x4d/0x330 kernel/workqueue.c:2421
 kthread+0x119/0x130 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:294