[syzbot] [bluetooth?] WARNING in hci_conn_drop (2)

[syzbot <syzbot+a2ab250fa8de8ee78a3f@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    e0f4c8dd9d2d Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=143350f4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=868079b7b8989c3c
dashboard link: https://syzkaller.appspot.com/bug?extid=a2ab250fa8de8ee78a3f
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/463c704c2ee6/disk-e0f4c8dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1bb99dd967d9/vmlinux-e0f4c8dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/505fe552b9a8/Image-e0f4c8dd.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a2ab250fa8de8ee78a3f@syzkaller.appspotmail.com

------------[ cut here ]------------
workqueue: cannot queue hci_conn_timeout on wq hci4
WARNING: CPU: 1 PID: 26 at kernel/workqueue.c:2258 __queue_work+0xe38/0x1230 kernel/workqueue.c:2256
Modules linked in:
CPU: 1 UID: 0 PID: 26 Comm: kworker/1:1 Not tainted 6.15.0-rc4-syzkaller-ge0f4c8dd9d2d #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events l2cap_chan_timeout
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __queue_work+0xe38/0x1230 kernel/workqueue.c:2256
lr : __queue_work+0xe38/0x1230 kernel/workqueue.c:2256
sp : ffff8000977277c0
x29: ffff800097727810 x28: 1fffe0001aa28400 x27: ffff0000d53712c0
x26: ffff0000ee275000 x25: dfff800000000000 x24: 0000000000000008
x23: ffff0000ee2751c0 x22: 0000000004208060 x21: 1fffe0001dc4ea38
x20: ffff800092804000 x19: ffff0000d4f38960 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ada5d6c x15: 0000000000000001
x14: 1fffe00036711ae2 x13: 0000000000000000 x12: 0000000000000000
x11: ffff600036711ae3 x10: 0000000000ff0100 x9 : 321ee84465be0000
x8 : 321ee84465be0000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800097727118 x4 : ffff80008f3f4fa0 x3 : ffff8000807ab99c
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
 __queue_work+0xe38/0x1230 kernel/workqueue.c:2256 (P)
 __queue_delayed_work+0xfc/0x2c8 kernel/workqueue.c:2509
 queue_delayed_work_on+0xe4/0x194 kernel/workqueue.c:2561
 queue_delayed_work include/linux/workqueue.h:677 [inline]
 hci_conn_drop+0x174/0x280 include/net/bluetooth/hci_core.h:1663
 l2cap_chan_del+0x228/0x470 net/bluetooth/l2cap_core.c:671
 l2cap_chan_close+0x424/0x684 net/bluetooth/l2cap_core.c:-1
 l2cap_chan_timeout+0x120/0x280 net/bluetooth/l2cap_core.c:431
 process_one_work+0x7e8/0x156c kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862
irq event stamp: 104354
hardirqs last  enabled at (104353): [<ffff8000804152dc>] __cancel_work+0x158/0x218 kernel/workqueue.c:4344
hardirqs last disabled at (104354): [<ffff80008041090c>] queue_delayed_work_on+0x54/0x194 kernel/workqueue.c:2557
softirqs last  enabled at (104348): [<ffff800089026b4c>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (104348): [<ffff800089026b4c>] release_sock+0x14c/0x1ac net/core/sock.c:3726
softirqs last disabled at (104346): [<ffff800089026a34>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (104346): [<ffff800089026a34>] release_sock+0x34/0x1ac net/core/sock.c:3715
---[ end trace 0000000000000000 ]---


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