syzbot

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kernfs: can not remove 'nr_tags', no directory
WARNING: CPU: 1 PID: 3630 at fs/kernfs/dir.c:1580 kernfs_remove_by_name_ns+0xb0/0xe0 fs/kernfs/dir.c:1579
Modules linked in:
CPU: 1 PID: 3630 Comm: syz-executor173 Not tainted 6.0.0-rc4-syzkaller-00302-gb96fbd602d35 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
RIP: 0010:kernfs_remove_by_name_ns+0xb0/0xe0 fs/kernfs/dir.c:1579
Code: 48 89 c3 e8 22 a9 74 ff 48 89 df e8 aa e5 ff ff 31 db eb 29 e8 11 a9 74 ff 48 c7 c7 c0 12 c0 8a 4c 89 fe 31 c0 e8 40 81 3c ff <0f> 0b bb fe ff ff ff eb 12 e8 f2 a8 74 ff bb fe ff ff ff 4c 89 e7
RSP: 0018:ffffc900038df9a8 EFLAGS: 00010246
RAX: 206ee7f3862b3300 RBX: ffffffff8d346b20 RCX: ffff888027301d80
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff816d5c8d R09: ffffed1017364f14
R10: ffffed1017364f14 R11: 1ffff11017364f13 R12: ffffffff8d346ae8
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff8b084ae0
FS:  00007fea237ba700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fea2384e4c0 CR3: 0000000071fce000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kernfs_remove_by_name include/linux/kernfs.h:615 [inline]
 remove_files fs/sysfs/group.c:28 [inline]
 sysfs_remove_group+0x102/0x2b0 fs/sysfs/group.c:288
 sysfs_remove_groups+0x5b/0xb0 fs/sysfs/group.c:312
 __kobject_del+0x84/0x300 lib/kobject.c:579
 kobject_del+0x41/0x60 lib/kobject.c:611
 blk_mq_unregister_hctx block/blk-mq-sysfs.c:181 [inline]
 blk_mq_sysfs_unregister_hctxs+0x235/0x320 block/blk-mq-sysfs.c:302
 __blk_mq_update_nr_hw_queues block/blk-mq.c:4548 [inline]
 blk_mq_update_nr_hw_queues+0x647/0x12d0 block/blk-mq.c:4594
 nbd_start_device+0x15d/0xb70 drivers/block/nbd.c:1357
 nbd_start_device_ioctl drivers/block/nbd.c:1407 [inline]
 __nbd_ioctl drivers/block/nbd.c:1481 [inline]
 nbd_ioctl+0x3b3/0xa40 drivers/block/nbd.c:1521
 blkdev_ioctl+0x3a6/0x760 block/ioctl.c:614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fea2380d319
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fea237ba2e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fea238914e0 RCX: 00007fea2380d319
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000007
RBP: 00007fea2385e194 R08: 0000000000000002 R09: 0000000000003932
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fea238914ec
R13: 00007fea237ba2f0 R14: 00007fea238914e8 R15: 0000000000000002
 </TASK>