EXT4-fs (loop4): mount failed
EXT4-fs error (device loop3): ext4_fill_super:4962: inode #2: comm syz-executor.3: iget: special inode unallocated
EXT4-fs (loop3): get root inode failed
EXT4-fs (loop3): mount failed
INFO: task syz-executor.2:12294 blocked for more than 143 seconds.
      Not tainted 5.10.201 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:27648 pid:12294 ppid:   287 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3800 [inline]
 __schedule+0x824/0x1ea0 kernel/sched/core.c:4548
 schedule+0xcb/0x270 kernel/sched/core.c:4626
 schedule_timeout+0x301/0x380 kernel/time/timer.c:1853
 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+0x168/0x270 kernel/sched/completion.c:138
 kthread_stop+0x160/0x4d0 kernel/kthread.c:642
 ext4_stop_mmpd+0x47/0xd0 fs/ext4/mmp.c:263
 ext4_fill_super+0x8414/0xd350 fs/ext4/super.c:5184
 mount_bdev+0x336/0x400 fs/super.c:1429
 legacy_get_tree+0x105/0x220 fs/fs_context.c:593
 vfs_get_tree+0x8e/0x300 fs/super.c:1559
 do_new_mount fs/namespace.c:2899 [inline]
 path_mount+0x13be/0x20b0 fs/namespace.c:3229
 do_mount fs/namespace.c:3242 [inline]
 __do_sys_mount fs/namespace.c:3450 [inline]
 __se_sys_mount fs/namespace.c:3427 [inline]
 __x64_sys_mount+0x282/0x300 fs/namespace.c:3427
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x62/0xc7
RIP: 0033:0x7f4a8fea704a
RSP: 002b:00007f4a8d41afa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f4a8fea704a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f4a8d41b000
RBP: 00007f4a8d41b040 R08: 00007f4a8d41b040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f4a8d41b000 R15: 0000000020000080

Showing all locks held in the system:
1 lock held by khungtaskd/22:
 #0: ffffffff84ff8560 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x27b kernel/locking/lockdep.c:6390
1 lock held by systemd-journal/103:
1 lock held by in:imklog/179:
2 locks held by rs:main Q:Reg/180:
1 lock held by syz-executor.2/12294:
 #0: ffff88803fb320e0 (&type->s_umount_key#21/1){+.+.}-{3:3}, at: alloc_super+0x1e5/0xa90 fs/super.c:229

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