syzbot

 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
kobject: kobject_add_internal failed for hci0:0 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci0: failed to register connection device
Bluetooth: hci0: command 0x2016 tx timeout
------------[ cut here ]------------
refcnt < 0
WARNING: net/bluetooth/hci_conn.c:634 at hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:634, CPU#1: kworker/u9:3/5784
Modules linked in:
CPU: 1 UID: 0 PID: 5784 Comm: kworker/u9:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: hci0 hci_conn_timeout
RIP: 0010:hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:634
Code: 48 89 df e8 23 b6 09 00 eb 07 e8 5c 0e 27 f7 b0 13 0f b6 f0 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 97 9c fe ff e8 42 0e 27 f7 90 <0f> 0b 90 eb 8c 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 31 ff ff ff
RSP: 0018:ffffc9000300fab0 EFLAGS: 00010293
RAX: ffffffff8a9ea7be RBX: ffff8880781a8000 RCX: ffff88802d6d0000
RDX: 0000000000000000 RSI: 00000000ffffffc1 RDI: 0000000000000000
RBP: 00000000ffffffc1 R08: ffff8880781a8013 R09: 1ffff1100f035002
R10: dffffc0000000000 R11: ffffed100f035003 R12: dffffc0000000000
R13: ffff8880781a8a40 R14: ffff8880781a8a40 R15: ffff8880781a8010
FS:  0000000000000000(0000) GS:ffff888125387000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1490f623c0 CR3: 000000000e74a000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x389/0x470 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>