FAT-fs (loop4): bogus logical sector size 514
FAT-fs (loop4): Can't find a valid FAT filesystem
loop4: detected capacity change from 0 to 512
FAT-fs (loop4): bogus logical sector size 514
FAT-fs (loop4): Can't find a valid FAT filesystem
INFO: task syz-executor.6:17516 blocked for more than 143 seconds.
      Not tainted 5.10.238 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.6  state:D stack:27800 pid:17516 ppid:  4803 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3799 [inline]
 __schedule+0x824/0x1ea0 kernel/sched/core.c:4547
 schedule+0xcb/0x270 kernel/sched/core.c:4625
 schedule_timeout+0x301/0x380 kernel/time/timer.c:1883
 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:657
 ext4_stop_mmpd+0x47/0xd0 fs/ext4/mmp.c:263
 ext4_fill_super+0x8407/0xd350 fs/ext4/super.c:5188
 mount_bdev+0x336/0x400 fs/super.c:1442
 legacy_get_tree+0x105/0x220 fs/fs_context.c:593
 vfs_get_tree+0x8e/0x300 fs/super.c:1572
 do_new_mount fs/namespace.c:2915 [inline]
 path_mount+0x1429/0x2120 fs/namespace.c:3245
 do_mount fs/namespace.c:3258 [inline]
 __do_sys_mount fs/namespace.c:3466 [inline]
 __se_sys_mount fs/namespace.c:3443 [inline]
 __x64_sys_mount+0x282/0x300 fs/namespace.c:3443
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x67/0xd1
RIP: 0033:0x7f497ff7604a
RSP: 002b:00007f497d4e9fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f497ff7604a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f497d4ea000
RBP: 00007f497d4ea040 R08: 00007f497d4ea040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f497d4ea000 R15: 0000000020012b00

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0: ffffffff84ff9160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x27b kernel/locking/lockdep.c:6410
1 lock held by systemd-journal/103:
1 lock held by in:imklog/177:
 #0: ffff88800ce22ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xf1/0x190 fs/file.c:994
2 locks held by agetty/219:
 #0: ffff888016ca7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x90 drivers/tty/tty_ldisc.c:267
 #1: ffffc900007e52e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xf22/0x14e0 drivers/tty/n_tty.c:2209
1 lock held by syz-executor.6/17516:
 #0: ffff88805e8500e0 (&type->s_umount_key#21/1){+.+.}-{3:3}, at: alloc_super+0x1e5/0xa90 fs/super.c:229

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