------------[ cut here ]------------ WARNING: block/blk-wbt.c:741 at wbt_init_enable_default+0x4e/0x60 block/blk-wbt.c:741, CPU#0: syz.1.1339/12295 Modules linked in: CPU: 0 UID: 0 PID: 12295 Comm: syz.1.1339 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:ffffc90003e9fb88 EFLAGS: 00010287 RAX: 000000000000d9e1 RBX: 00000000fffffff4 RCX: ffffc90004e02000 RDX: 0000000000080000 RSI: ffffffff849bd4bd RDI: 0000000000000005 RBP: ffff88805b270000 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000fffffff4 R11: ffffffff81000130 R12: ffff888028574c40 R13: ffff88805b270390 R14: ffff888028574c50 R15: ffff88805b270090 FS: 00007fb62a83d6c0(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb6299ee470 CR3: 0000000029cb0000 CR4: 00000000003526f0 Call Trace: 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: 0033:0x7fb62998f7c9 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:00007fb62a83d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb629be5fa0 RCX: 00007fb62998f7c9 RDX: fffffffffffffffd RSI: 0000000000004c80 RDI: 0000000000000003 RBP: 00007fb629a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb629be6038 R14: 00007fb629be5fa0 R15: 00007fff035fb808