[moderation] [bluetooth?] BUG: workqueue leaked atomic, lock or RCU: kworker/u9:NUM[NUM]

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 642a16ca7994 Add linux-next specific files for 20240627
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16d59701980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ba15715f73169384
dashboard link: https://syzkaller.appspot.com/bug?extid=63d1d2984fb00d651ead
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [johan....@gmail.com linux-b...@vger.kernel.org linux-...@vger.kernel.org luiz....@gmail.com mar...@holtmann.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/72ed10c6e9be/disk-642a16ca.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f2ca81ede1c4/vmlinux-642a16ca.xz
kernel image: https://storage.googleapis.com/syzbot-assets/af14c94fa854/bzImage-642a16ca.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+63d1d2...@syzkaller.appspotmail.com

BUG: workqueue leaked atomic, lock or RCU: kworker/u9:2[5095]
preempt=0x00000000 lock=0->1 RCU=0->0 workfn=hci_rx_work
1 lock held by kworker/u9:2/5095:
#0: ffff88802b7fc518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
#0: ffff88802b7fc518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_conless_channel net/bluetooth/l2cap_core.c:6764 [inline]
#0: ffff88802b7fc518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_recv_frame+0x7ce/0x10840 net/bluetooth/l2cap_core.c:6830
CPU: 0 UID: 0 PID: 5095 Comm: kworker/u9:2 Not tainted 6.10.0-rc5-next-20240627-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: hci6 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
process_one_work kernel/workqueue.c:3245 [inline]
process_scheduled_works+0x1121/0x1830 kernel/workqueue.c:3305
worker_thread+0x86d/0xd40 kernel/workqueue.c:3383
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>


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