On Wed, Nov 6, 2013 at 11:38 PM, Jiri Kosina <jkosina@xxxxxxx> 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. Here is the relevant lsusb output that I think contains what you're asking for (I had to unbind usbhid for it to include the descriptor): Bus 005 Device 003: ID 05ac:8240 Apple, Inc. Built-in IR Receiver Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 8 idVendor 0x05ac Apple, Inc. idProduct 0x8240 Built-in IR Receiver bcdDevice 1.10 iManufacturer 1 Apple Computer, Inc. iProduct 2 IR Receiver iSerial 0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 34 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xa0 (Bus Powered) Remote Wakeup MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 0 No Subclass bInterfaceProtocol 0 None iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 1.11 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 41 Report Descriptor: (length is 41) Item(Global): Usage Page, data= [ 0x00 0xff ] 65280 (null) Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0xff 0x00 ] 255 Item(Global): Report Size, data= [ 0x08 ] 8 Item(Global): Report Count, data= [ 0x04 ] 4 Item(Global): Report ID, data= [ 0x24 ] 36 Item(Local ): Usage, data= [ 0x00 ] 0 (null) Item(Main ): Input, data= [ 0x22 ] 34 Data Variable Absolute No_Wrap Linear No_Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Size, data= [ 0x08 ] 8 Item(Global): Report Count, data= [ 0x04 ] 4 Item(Global): Report ID, data= [ 0x25 ] 37 Item(Local ): Usage, data= [ 0x00 ] 0 (null) Item(Main ): Input, data= [ 0x22 ] 34 Data Variable Absolute No_Wrap Linear No_Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Size, data= [ 0x08 ] 8 Item(Global): Report Count, data= [ 0x04 ] 4 Item(Global): Report ID, data= [ 0x26 ] 38 Item(Local ): Usage, data= [ 0x00 ] 0 (null) Item(Main ): Input, data= [ 0x22 ] 34 Data Variable Absolute No_Wrap Linear No_Preferred_State No_Null_Position Non_Volatile Bitfield Item(Main ): End Collection, data=none Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 10 Device Status: 0x0000 (Bus Powered) James. -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
