INFO: task syz.0.23:5029 blocked for more than 143 seconds.
      Not tainted 5.15.185-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.23        state:D stack:25216 pid: 5029 ppid:  4821 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:5088
 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:3010
 do_mount fs/namespace.c:3353 [inline]
 __do_sys_mount fs/namespace.c:3561 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3538
 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: 0033:0x7f44cbdfa90a
RSP: 002b:00007f44cb069e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f44cb069ef0 RCX: 00007f44cbdfa90a
RDX: 0000400000000040 RSI: 0000400000000000 RDI: 00007f44cb069eb0
RBP: 0000400000000040 R08: 00007f44cb069ef0 R09: 0000000003010008
R10: 0000000003010008 R11: 0000000000000246 R12: 0000400000000000
R13: 00007f44cb069eb0 R14: 0000000000000538 R15: 0000400000000340
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11bfa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:5/3071:
2 locks held by getty/3932:
 #0: ffff88802c04f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002ce62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz.0.23/5029:
 #0: ffff88807ae220e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.1.24/5075:
 #0: ffff8880716a80e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.2.30/5107:
 #0: ffff88807ea0a0e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.3.34/5138:
 #0: ffff8880598760e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.4.35/5161:
 #0: ffff8880765560e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.5.44/5205:
 #0: ffff888078cc20e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.6.50/5244:
 #0: ffff888058c500e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.7.51/5273:
 #0: ffff88807bb6c0e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.8.59/5315:
 #0: ffff88807e3700e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.185-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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4878 Comm: kworker/1:20 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker
RIP: 0010:register_lock_class+0x12d/0x880 kernel/locking/lockdep.c:1337
Code: 48 c1 e9 03 42 0f b6 0c 29 84 c9 0f 85 dd 05 00 00 83 3d b5 51 ae 14 00 75 21 4c 8d 70 48 4c 89 f1 48 c1 e9 03 42 0f b6 0c 29 <84> c9 0f 85 e8 05 00 00 41 39 1e 0f 85 79 01 00 00 48 c7 44 24 40
RSP: 0018:ffffc900030af7c0 EFLAGS: 00000802
RAX: ffffffff8f98c400 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffffffff960a1f03 RSI: 0000000000000001 RDI: ffffc900030afd00
RBP: ffffc900030af890 R08: dffffc0000000000 R09: 0000000000000000
R10: fffffbfff1ad157e R11: 1ffffffff1ad157d R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8f98c448 R15: 1ffff92000615f00
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f927cc4a000 CR3: 000000002aaa1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __lock_acquire+0x160/0x7c60 kernel/locking/lockdep.c:4891
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 process_one_work+0x7bf/0x1000 kernel/workqueue.c:2286
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>