[syzbot] WARNING: bad unlock balance in hub_event

From: syzbot
Date: Mon Nov 22 2021 - 00:51:25 EST


Hello,

syzbot found the following issue on:

HEAD commit: 5191249f8803 Add linux-next specific files for 20211118
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=102c939eb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=fca39774e64812b0
dashboard link: https://syzkaller.appspot.com/bug?extid=423eaf1efaa99fb8ce96
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+423eaf1efaa99fb8ce96@xxxxxxxxxxxxxxxxxxxxxxxxx

=====================================
WARNING: bad unlock balance detected!
5.16.0-rc1-next-20211118-syzkaller #0 Not tainted
-------------------------------------
kworker/1:24/10009 is trying to release lock (hcd->address0_mutex) at:
[<ffffffff856171ad>] hub_port_connect drivers/usb/core/hub.c:5402 [inline]
[<ffffffff856171ad>] hub_port_connect_change drivers/usb/core/hub.c:5493 [inline]
[<ffffffff856171ad>] port_event drivers/usb/core/hub.c:5639 [inline]
[<ffffffff856171ad>] hub_event+0x2a9d/0x4450 drivers/usb/core/hub.c:5721
but there are no more locks to release!

other info that might help us debug this:
3 locks held by kworker/1:24/10009:
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
#0: ffff888012baf138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
#1: ffffc9000b9f7db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
#2: ffff888147b82220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888147b82220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4450 drivers/usb/core/hub.c:5667

stack backtrace:
CPU: 1 PID: 10009 Comm: kworker/1:24 Not tainted 5.16.0-rc1-next-20211118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline]
__lock_release kernel/locking/lockdep.c:5316 [inline]
lock_release.cold+0x34/0x4e kernel/locking/lockdep.c:5657
__mutex_unlock_slowpath+0x99/0x5e0 kernel/locking/mutex.c:900
hub_port_connect drivers/usb/core/hub.c:5402 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5493 [inline]
port_event drivers/usb/core/hub.c:5639 [inline]
hub_event+0x2a9d/0x4450 drivers/usb/core/hub.c:5721
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
process_scheduled_works kernel/workqueue.c:2361 [inline]
worker_thread+0x85c/0x11f0 kernel/workqueue.c:2447
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>


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