Message-ID: <672c2a44.050a0220.350062.0283.GAE@google.com>
Date: Wed, 06 Nov 2024 18:47:32 -0800
From: syzbot <syzbot+a95fab8e491d4ac8cbe9@...kaller.appspotmail.com>
To: axboe@...nel.dk, linux-block@...r.kernel.org, linux-kernel@...r.kernel.org, 
	linux-usb@...r.kernel.org, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [block?] [usb?] WARNING: bad unlock balance in elevator_init_mq

Hello,

syzbot found the following issue on:

HEAD commit:    c88416ba074a Add linux-next specific files for 20241101
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16e21aa7980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=704b6be2ac2f205f
dashboard link: https://syzkaller.appspot.com/bug?extid=a95fab8e491d4ac8cbe9
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1722ab40580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/760a8c88d0c3/disk-c88416ba.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/46e4b0a851a2/vmlinux-c88416ba.xz
kernel image: https://storage.googleapis.com/syzbot-assets/428e2c784b75/bzImage-c88416ba.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a95fab8e491d4ac8cbe9@...kaller.appspotmail.com

sd 4:0:0:1: [sdb] 0-byte physical blocks
sd 4:0:0:1: [sdb] Test WP failed, assume Write Enabled
sd 4:0:0:1: [sdb] Asking for cache data failed
sd 4:0:0:1: [sdb] Assuming drive cache: write through
=====================================
WARNING: bad unlock balance detected!
6.12.0-rc5-next-20241101-syzkaller #0 Not tainted
-------------------------------------
kworker/u8:4/67 is trying to release lock (&q->q_usage_counter(queue)) at:
[<ffffffff849207a2>] elevator_init_mq+0x1e2/0x2d0 block/elevator.c:607
but there are no more locks to release!

other info that might help us debug this:
3 locks held by kworker/u8:4/67:
 #0: ffff88801d681148 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801d681148 ((wq_completion)async){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc900020bfd00 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc900020bfd00 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
 #2: ffff8880327ca378 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline]
 #2: ffff8880327ca378 (&dev->mutex){....}-{4:4}, at: __device_attach_async_helper+0xfc/0x300 drivers/base/dd.c:973

stack backtrace:
CPU: 1 UID: 0 PID: 67 Comm: kworker/u8:4 Not tainted 6.12.0-rc5-next-20241101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: async async_run_entry_fn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_unlock_imbalance_bug+0x25b/0x2d0 kernel/locking/lockdep.c:5287
 __lock_release kernel/locking/lockdep.c:5526 [inline]
 lock_release+0x5cb/0xa30 kernel/locking/lockdep.c:5870
 blk_unfreeze_release_lock block/blk.h:745 [inline]
 blk_mq_unfreeze_queue+0xd2/0x140 block/blk-mq.c:213
 elevator_init_mq+0x1e2/0x2d0 block/elevator.c:607
 add_disk_fwnode+0x10d/0xf80 block/genhd.c:413
 sd_probe+0xba6/0x1100 drivers/scsi/sd.c:4024
 really_probe+0x2b8/0xad0 drivers/base/dd.c:658
 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
 driver_probe_device+0x50/0x430 drivers/base/dd.c:830
 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958
 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459
 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987
 async_run_entry_fn+0xa8/0x420 kernel/async.c:129
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
sd 4:0:0:1: [sdb] Attached SCSI removable disk
sd 5:0:0:0: [sdc] Media removed, stopped polling
sd 5:0:0:0: [sdc] Attached SCSI removable disk
sd 2:0:0:0: [sdb] Media removed, stopped polling
sd 2:0:0:0: [sdb] Attached SCSI removable disk
sd 1:0:0:0: [sdb] Media removed, stopped polling
sd 1:0:0:0: [sdb] Attached SCSI removable disk
sd 4:0:0:0: [sdb] Media removed, stopped polling
sd 4:0:0:0: [sdb] Attached SCSI removable disk
sd 1:0:0:1: [sdf] Media removed, stopped polling
sd 1:0:0:1: [sdf] Attached SCSI removable disk


---
This report is generated by a bot. It may contain errors.
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