Re: [appleir] BUG: unable to handle kernel NULL pointer dereference

[Bastien Nocera <hadess@hadess.net>]

On Wed, 2013-11-06 at 16:38 +0100, Jiri Kosina wrote:
> On Tue, 29 Oct 2013, Luis Henriques wrote:
> 
> > James has reported a NULL pointer dereference[1] on the appleir
> > driver.  From the bug report[2] it looks like it is 100%
> > reproducible using a 3.12-rc6 kernel simply by pressing any button on
> > the IR remote.
> > 
> > >From the stack trace, it looks like input_event is invoked with the
> > input_dev parameter set to NULL, which seems to indicate that
> > appleir_input_configured is never invoked.
> > 
> > Any ideas?
> > 
> > [1] https://launchpadlibrarian.net/154942024/macmini-oops.jpg
> > [2] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1244505
> 
> [ adding some more CCs ]
> 
> Okay, so apparently we didn't register with input, but only hiddev / 
> hidraw.
> 
> appleir 0003:05AC:8240.0005: hiddev0,hidraw4: USB HID v1.11 Device [Apple Computer, Inc. IR Receiver] on usb-0000:00:1d.3-2/input0
> 
> Therefore ->input_configured() callback has never been called, and thus we 
> oops due to appleir->input_dev being NULL when the first raw event is 
> reported.
> 
> Could you please provide report descriptor of the device?
> 
> The driver apparently relies on it being registered with hid-input, but 
> for some reason that doesn't happen.

FWIW, my original patch (and driver) was an input driver, not a hid one.
I'm not sure either how the new driver got tested.