------------[ cut here ]------------ WARNING: block/blk-wbt.c:741 at wbt_init_enable_default+0x4e/0x60 block/blk-wbt.c:741, CPU#1: syz.7.2732/19684 Modules linked in: CPU: 1 UID: 0 PID: 19684 Comm: syz.7.2732 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [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: ff 89 c6 e8 b4 7a 40 fd 85 db 75 18 e8 6b 76 40 fd 5b c3 cc cc cc cc cc e8 5f 76 40 fd 5b c3 cc cc cc cc cc e8 53 76 40 fd 90 <0f> 0b 90 5b e9 99 6f dd 06 cc 0f 1f 84 00 00 00 00 00 90 90 90 90 RSP: 0018:ffffc9000b537a98 EFLAGS: 00010293 RAX: ffffffff84813bfd RBX: 00000000fffffff4 RCX: ffff8880342e9e80 RDX: 0000000000000000 RSI: 00000000fffffff4 RDI: 0000000000000000 RBP: 1ffff1100f9adc12 R08: ffffffff8f822077 R09: 1ffffffff1f0440e R10: dffffc0000000000 R11: fffffbfff1f0440f R12: 0000000000000000 R13: 1ffff1100522f4c6 R14: ffff88807cd6e000 R15: ffff88802917a620 FS: 00007f3932a7a6c0(0000) GS:ffff888125f35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000043280000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: blk_register_queue+0x36a/0x3f0 block/blk-sysfs.c:935 __add_disk+0x677/0xd50 block/genhd.c:528 add_disk_fwnode+0xfc/0x480 block/genhd.c:597 add_disk include/linux/blkdev.h:785 [inline] loop_add+0x7f0/0xad0 drivers/block/loop.c:2093 loop_control_ioctl+0x128/0x5a0 drivers/block/loop.c:2220 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3931b8f749 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:00007f3932a7a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3931de6180 RCX: 00007f3931b8f749 RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000006 RBP: 00007f3931c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3931de6218 R14: 00007f3931de6180 R15: 00007f3931f0fa28