Re: [PATCH] Wait for child devices to go away before deleting a connection

[Marcel Holtmann <marcel@holtmann.org>]

Hi Brian,

> >>>>> Kay, David, wouldn't be pinning of the parent device here be enough to
> >>>>> get this done in a clean way?
> >>>>>   
> >>>>>       
> >>>>>           
> >>>> If there's a way that the connection can be pinned until the child 
> >>>> devices go away, that definitely sounds cleaner to me.
> >>>>     
> >>>>         
> >>> so I pushed some patches to bluetooth-testing tree that should fix this
> >>> problem. They are not fully tested by me. Please test and report back
> >>> the results.
> >>>   
> >>>       
> >> Fails to compile if CONFIG_USB_HIDDEV=y :
> >>
> >> ERROR: "hiddev_disconnect" [net/bluetooth/hidp/hidp.ko] undefined!
> >>
> >> Ironically, the reference to hiddev_disconnect is fine if hiddev isn't 
> >> enabled because then hiddev.h supplies an empty static inline function.
> >>
> >> I'm going to test with a kernel without hiddev for now.
> >>     
> >
> > just take that piece out of the patch. It is not important. I just wanna
> > now if the uevents are now coming in order.
> >   
> 
> I just tried it without hiddev and observed that the input devices go 
> away, but the connection never gets deleted. Then when I turn my mouse 
> back on, bad stuff happens:

I do have a typo here :(

	void hci_conn_hold_device(struct hci_conn *conn)
	{
	        hci_conn_hold(conn);

	        atomic_inc(&conn->devref);
	}
	EXPORT_SYMBOL(hci_conn_hold_device);

	void hci_conn_put_device(struct hci_conn *conn)
	{
	        if (atomic_dec_and_test(&conn->refcnt))
        	        hci_conn_del_sysfs(conn);

        	hci_conn_put(conn);
	}
	EXPORT_SYMBOL(hci_conn_put_device);

The atomic_dec_and_test() should operate on conn->devref. Can you change
that and try again.

Also if that doesn't help, remove the hci_conn_hold() and hci_conn_put()
from the two functions above and try again.

Regards

Marcel