INFO: task syz.7.1028:9609 blocked for more than 144 seconds.
      Not tainted 5.15.189-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1028      state:D stack:24800 pid: 9609 ppid:  6183 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x97/0x280 kernel/time/timer.c:1890
 do_wait_for_common+0x29a/0x440 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 kthread_stop+0x16e/0x540 kernel/kthread.c:666
 ext4_stop_mmpd+0x43/0xb0 fs/ext4/mmp.c:263
 ext4_fill_super+0x6608/0x9a00 fs/ext4/super.c:5086
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3014
 do_mount fs/namespace.c:3357 [inline]
 __do_sys_mount fs/namespace.c:3565 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3542
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8bf292d14a
RSP: 002b:00007f8bf0750e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f8bf0750ef0 RCX: 00007f8bf292d14a
RDX: 0000200000000040 RSI: 0000200000000000 RDI: 00007f8bf0750eb0
RBP: 0000200000000040 R08: 00007f8bf0750ef0 R09: 0000000002010008
R10: 0000000002010008 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f8bf0750eb0 R14: 000000000000052e R15: 00002000000001c0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/1:2/1110:
 #0: ffff88801b9c9138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90004abfd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff888023ee3220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff888023ee3220 (&dev->mutex){....}-{3:3}, at: hub_event+0x18f/0x4fa0 drivers/usb/core/hub.c:5781
2 locks held by getty/3951:
 #0: ffff88802c669098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
4 locks held by udevd/4176:
 #0: ffff88804f97f0a0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
 #1: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #2: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #3: ffff88807d7eeca8 (&ep->wq){....}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline]
 #3: ffff88807d7eeca8 (&ep->wq){....}-{2:2}, at: __wake_up_sync_key kernel/sched/wait.c:205 [inline]
 #3: ffff88807d7eeca8 (&ep->wq){....}-{2:2}, at: __wake_up_sync+0xeb/0x180 kernel/sched/wait.c:237
1 lock held by syz.7.1028/9609:
 #0: ffff88801afb60e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.0.1353/11363:
1 lock held by sed/11411:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11415 Comm: dhcpcd-run-hook Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0x2d2/0x760 kernel/locking/lockdep.c:4278
Code: 00 00 fc ff df e9 62 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c 99 48 89 df e8 2a 63 60 00 48 ba 00 00 00 00 00 fc ff df eb 85 <48> 8b 44 24 10 4c 8d b8 d0 0a 00 00 4c 89 f8 48 c1 e8 03 0f b6 04
RSP: 0018:ffffc90002eef8a0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88807d83e428 RCX: 868c61c357916300
RDX: dffffc0000000000 RSI: ffffffff8a0b23c0 RDI: ffffffff8a599340
RBP: ffffc90002eef950 R08: ffffffff89c000ca R09: 0000000000000003
R10: 000000008cdd3901 R11: 000000009f1b9f86 R12: ffff888140007140
R13: ffff88801ecec9a0 R14: 1ffff1100fb07c85 R15: 0000000000000286
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff00925128 CR3: 000000001f092000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
 kasan_quarantine_put+0xd4/0x220 mm/kasan/quarantine.c:231
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kmem_cache_free+0x8f/0x210 mm/slub.c:3515
 anon_vma_chain_free mm/rmap.c:143 [inline]
 unlink_anon_vmas+0x611/0x660 mm/rmap.c:443
 free_pgtables+0x177/0x2a0 mm/memory.c:426
 exit_mmap+0x39e/0x5f0 mm/mmap.c:3213
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x567/0x6c0 kernel/exit.c:550
 do_exit+0x5a1/0x20a0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7faa54e366c5
Code: Unable to access opcode bytes at RIP 0x7faa54e3669b.
RSP: 002b:00007fff00925038 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fff00925304 RCX: 00007faa54e366c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007fff00925130 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff00925370 R14: 00007faa5503e000 R15: 000055fa84a31d98
 </TASK>