------------[ cut here ]------------
WARNING: block/blk-wbt.c:741 at wbt_init_enable_default+0x4e/0x60 block/blk-wbt.c:741, CPU#1: syz.2.3185/20944
Modules linked in:
CPU: 1 UID: 0 PID: 20944 Comm: syz.2.3185 Tainted: G     U       L      syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:wbt_init_enable_default+0x4e/0x60 block/blk-wbt.c:741
Code: 07 5b 5d e9 54 96 22 fd e8 4f 96 22 fd 48 89 ef e8 77 fa ff ff 31 ff 89 c3 89 c6 e8 dc 90 22 fd 85 db 74 dd e8 33 96 22 fd 90 <0f> 0b 90 eb d2 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90
RSP: 0018:ffffc90004cafb88 EFLAGS: 00010283
RAX: 000000000000dfdc RBX: 00000000fffffff4 RCX: ffffc9000fc71000
RDX: 0000000000080000 RSI: ffffffff849bd4bd RDI: 0000000000000005
RBP: ffff88805d620000 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000fffffff4 R11: ffffffff81000130 R12: ffff888029cf2fa8
R13: ffff88805d620390 R14: ffff888029cf2fb8 R15: ffff88805d620090
FS:  00007fb36040e6c0(0000) GS:ffff8881249fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb35f5ee470 CR3: 000000002b140000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 blk_register_queue+0x39e/0x4e0 block/blk-sysfs.c:935
 __add_disk+0x74a/0xf00 block/genhd.c:528
 add_disk_fwnode+0x13f/0x5d0 block/genhd.c:597
 add_disk include/linux/blkdev.h:785 [inline]
 loop_add+0x903/0xb70 drivers/block/loop.c:2093
 loop_control_ioctl+0x13e/0x640 drivers/block/loop.c:2220
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb35f58f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb36040e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb35f7e5fa0 RCX: 00007fb35f58f7c9
RDX: fffffffffffffffd RSI: 0000000000004c80 RDI: 0000000000000003
RBP: 00007fb35f613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb35f7e6038 R14: 00007fb35f7e5fa0 R15: 00007fff8beba7b8
 </TASK>