INFO: task syz.4.11948:27135 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.11948     state:D
 stack:28120 pid:27135 tgid:27134 ppid:23242  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 bdev_open+0xe0/0xd30
 blkdev_open+0x470/0x610
 do_dentry_open+0x785/0x14e0
 vfs_open+0x3b/0x340
 path_openat+0x2e08/0x3860
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92bc15d60e
RSP: 002b:00007f92bd11db28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f92bd11e6c0 RCX: 00007f92bc15d60e
RDX: 0000000000103880 RSI: 00007f92bd11dc00 RDI: ffffffffffffff9c
RBP: 00007f92bd11dc00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f92bc416038 R14: 00007f92bc415fa0 R15: 00007ffcb88ddd58
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by udevd/30248:
 #0: ffff888103bdd350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by kworker/u8:6/25263:
 #0: ffff8881012b5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc9000889fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdc0a88 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffff8881b5ef5128 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420
 #4: ffff8881b5ef7258 (&devlink->lock_key#79){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420
 #5: ffffffff8e962f78 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580
1 lock held by syz-executor/16384:
 #0: ffffffff8e9630a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
2 locks held by getty/25992:
 #0: ffff8881762ea0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900017ee2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
1 lock held by syz.4.11948/27135:
 #0: ffff888103bdd350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.7.12485/357:
 #0: ffffffff8e9630a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16384 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:deref_stack_reg+0x1b3/0x230
Code: 39 f0 0f 96 c0 20 c8 3c 01 75 30 4c 89 c7 49 89 f7 e8 11 08 00 00 49 89 c6 48 8b 5c 24 18 48 89 d8 48 c1 e8 03 42 80 3c 38 00 <74> 08 48 89 df e8 d3 f3 b9 00 4c 89 33 b0 01 eb 02 31 c0 48 83 c4
RSP: 0018:ffffc90022d3ed20 EFLAGS: 00000246
RAX: 1ffff920045a7dd1 RBX: ffffc90022d3ee88 RCX: 0000000000000001
RDX: ffffc90022d3ee88 RSI: dffffc0000000000 RDI: ffffc90022d3f950
RBP: 1ffff920045a7dc9 R08: ffffc90022d3f950 R09: 0000000000000000
R10: ffffc90022d3ee98 R11: fffff520045a7dd5 R12: 1ffff920045a7dca
R13: 1ffff920045a7dcb R14: 0000000000000001 R15: dffffc0000000000
FS:  000055555599e500(0000) GS:ffff88818dc93000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4ac410a1d0 CR3: 000000016e59a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 unwind_next_frame+0x19d5/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 free_unref_folios+0xcdf/0x1430
 folios_put_refs+0xa3d/0xb80
 shmem_undo_range+0x52c/0x1660
 shmem_evict_inode+0x289/0xae0
 evict+0x61e/0xb10
 __dentry_kill+0x1a2/0x690
 shrink_kill+0xa9/0x2c0
 shrink_dentry_list+0x2e0/0x5e0
 shrink_dcache_tree+0xe9/0x5d0
 shrink_dcache_for_umount+0xa8/0x1f0
 generic_shutdown_super+0x6f/0x2d0
 kill_anon_super+0x3b/0x70
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 do_exit+0x70f/0x22c0
 do_group_exit+0x21b/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x221a/0x2240
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9ac3f9cdd9
Code: Unable to access opcode bytes at 0x7f9ac3f9cdaf.
RSP: 002b:00007ffc6afbea38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f9ac4033cb1 RCX: 00007f9ac3f9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f9ac4033cc3 R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00000000000927c0 R14: 00000000002ecb2e R15: 00007ffc6afbebe0
 </TASK>
