[syzbot] [block?] WARNING in blk_mq_unquiesce_queue

From: syzbot

Date: Mon Sep 07 2026 - 12:18:07 EST


Hello,

syzbot found the following issue on:

HEAD commit: 32b6ef9a5d0e Add linux-next specific files for 20260902
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1740f0f9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=32ceed1c94c11059
dashboard link: https://syzkaller.appspot.com/bug?extid=9ab4656e96793f987052
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/23067747792b/disk-32b6ef9a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/30cb2facc601/vmlinux-32b6ef9a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a4907bc6c937/bzImage-32b6ef9a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9ab4656e96793f987052@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
q->quiesce_depth <= 0
WARNING: block/blk-mq.c:321 at blk_mq_unquiesce_queue+0xdf/0x120 block/blk-mq.c:321, CPU#1: kworker/u8:3/50
Modules linked in:
CPU: 1 UID: 0 PID: 50 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: nvme-reset-wq nvme_loop_reset_ctrl_work
RIP: 0010:blk_mq_unquiesce_queue+0xdf/0x120 block/blk-mq.c:321
Code: 48 8b 34 24 e8 f2 04 2b 07 4c 89 ff be 01 00 00 00 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d e9 77 ed ff ff e8 02 92 09 fd 90 <0f> 0b 90 eb a2 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 5a ff ff ff
RSP: 0000:ffffc90000bb7a08 EFLAGS: 00010093
RAX: ffffffff84be42ae RBX: ffff88802a03e738 RCX: ffff88801b171f40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000176f2c R12: 1ffff11005407cef
R13: dffffc0000000000 R14: ffff88802a03e778 R15: ffff88802a03e670
FS: 0000000000000000(0000) GS:ffff888124dcb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555584f52a88 CR3: 0000000058f50000 CR4: 00000000003526f0
Call Trace:
<TASK>
blk_mq_unquiesce_tagset+0x134/0x220 block/blk-mq.c:357
nvme_loop_destroy_io_queues drivers/nvme/target/loop.c:313 [inline]
nvme_loop_shutdown_ctrl drivers/nvme/target/loop.c:412 [inline]
nvme_loop_reset_ctrl_work+0x1c7/0x810 drivers/nvme/target/loop.c:447
process_one_work kernel/workqueue.c:3399 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3482
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3563
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup