A bug was triggered in f2fs.
I will provide the triggering script soon.



--- Core dump ---
[   47.368206] kernel BUG at fs/f2fs/inode.c:722!
[   47.368833] invalid opcode: 0000 [#1] SMP KASAN PTI
[   47.369378] CPU: 0 PID: 2232 Comm: umount Not tainted 5.1.3 #10
[   47.370041] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[   47.371214] RIP: 0010:f2fs_evict_inode+0xa13/0xa60
[   47.371792] Code: e9 04 f9 ff ff 4c 8b 6c 24 38 e8 78 58 78 ff 31 ff 89 de e8 df 59 78 ff 85 db 0f 84 7e fd ff ff e9 1c ff ff ff e8 5d 58 78 ff <0f> 0b e8 56 58 78 ff 48 c7 c7 48 e0 ca 84 48 8b 5c 24 70 e8 05 94
[   47.374202] RSP: 0018:ffff888116897b50 EFLAGS: 00010293
[   47.374875] RAX: ffff888106af8000 RBX: 0000000000000001 RCX: ffffffff82c8cd53
[   47.375790] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
[   47.376708] RBP: ffff8880b9f5dc80 R08: ffff888106af8000 R09: ffffed1021198ab1
[   47.377651] R10: ffffed1021198ab0 R11: ffff888108cc5587 R12: ffff88811a576600
[   47.378545] R13: ffff8880b9f5ded0 R14: ffff8880b9f5df20 R15: ffff8880b9f5df00
[   47.379461] FS:  00007f151521ae40(0000) GS:ffff88811b400000(0000) knlGS:0000000000000000
[   47.380517] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   47.381229] CR2: 00007f1514df0cb1 CR3: 0000000106418000 CR4: 00000000000006f0
[   47.382131] Call Trace:
[   47.382404]  ? _raw_spin_lock_irq+0xd0/0xd0
[   47.382933]  ? f2fs_write_inode+0x5d0/0x5d0
[   47.383450]  evict+0x19c/0x340
[   47.383791]  dispose_list+0x72/0xa0
[   47.384239]  evict_inodes+0x2ce/0x310
[   47.384688]  ? dispose_list+0xa0/0xa0
[   47.385126]  ? filemap_write_and_wait+0x88/0xc0
[   47.385695]  ? __sync_blockdev+0x54/0x90
[   47.386140]  generic_shutdown_super+0x6c/0x1d0
[   47.386716]  kill_block_super+0x54/0x90
[   47.387170]  kill_f2fs_super+0x172/0x210
[   47.387632]  ? __f2fs_commit_super+0xc0/0xc0
[   47.388153]  ? xas_start+0xbf/0x1c0
[   47.388572]  ? unregister_shrinker+0x9e/0xc0
[   47.389009]  ? kfree+0x9b/0x1c0
[   47.389321]  deactivate_locked_super+0x69/0xc0
[   47.389751]  deactivate_super+0x14e/0x160
[   47.390141]  ? iterate_supers_type+0x1c0/0x1c0
[   47.390573]  cleanup_mnt+0x71/0xc0
[   47.390911]  task_work_run+0x100/0x120
[   47.391279]  exit_to_usermode_loop+0x175/0x180
[   47.391709]  do_syscall_64+0x1f1/0x230
[   47.392076]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   47.392668] RIP: 0033:0x7f1514afcd77
[   47.393272] Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f1 00 2b 00 f7 d8 64 89 01 48
[   47.395802] RSP: 002b:00007fffe97ea0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[   47.396839] RAX: 0000000000000000 RBX: 0000557449b4c500 RCX: 00007f1514afcd77
[   47.397809] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000557449b4c6e0
[   47.398773] RBP: 0000557449b4c6e0 R08: 0000557449b4c700 R09: 0000000000000014
[   47.399735] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f1514ffee64
[   47.400703] R13: 0000000000000000 R14: 0000000000000000 R15: 00007fffe97ea370
[   47.401665] Modules linked in:
[   47.402092] Dumping ftrace buffer:
[   47.402562]    (ftrace buffer empty)
[   47.403089] ---[ end trace 6f7cea09b723ae50 ]---