On Mon, Nov 21, 2016 at 02:19:32PM +0100, Oliver Neukum wrote: > On Thu, 2016-11-17 at 17:11 +0100, Wim Osterholt wrote: > > > Nov 17 15:07:51 localhost kernel: Check point 10 > > Nov 17 15:07:51 localhost kernel: BUG: unable to handle kernel NULL pointer dereference at 00000249 > > Nov 17 15:07:51 localhost kernel: IP: [<e186ece2>] acm_probe+0x559/0xe53 [cdc_acm] > > Nov 17 15:07:51 localhost kernel: *pde = 00000000 > > Nov 17 15:07:51 localhost kernel: Oops: 0000 [#1] SMP > > I don't understand it, bit please test the attached patch > with dynamic debugging for cdc-acm and the kernel log level > at maximum. And please repost "lsusb -v" for your device. I didn't find traces of kernel-4.9-rc5 being ran on any of my laptops, so I can't have seen a crash on rc5. It seems rc5 and rc6 is safe now. I assume you want this on a crashing kernel, but I already removed the sources. (Lack of space). 4.8.10 is now compiling, that was the fastest option. If that one doesn't crash anymore I'll dig up 4.8.8 again. lsusb -v: Bus 004 Device 002: ID 0572:1340 Conexant Systems (Rockwell), Inc. Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 1.10 bDeviceClass 2 Communications bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x0572 Conexant Systems (Rockwell), Inc. idProduct 0x1340 bcdDevice 1.00 iManufacturer 1 Conexant iProduct 2 USB Modem iSerial 3 12345678 bNumConfigurations 2 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 73 bNumInterfaces 2 bConfigurationValue 1 iConfiguration 0 bmAttributes 0x80 (Bus Powered) MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 2 Communications bInterfaceSubClass 2 Abstract (modem) bInterfaceProtocol 1 AT-commands (v.25ter) iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 128 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 10 CDC Data bInterfaceSubClass 0 Unused bInterfaceProtocol 0 iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 1 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x02 EP 2 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 1 CDC Header: bcdCDC 1.10 CDC Call Management: bmCapabilities 0x03 call management use DataInterface bDataInterface 1 CDC ACM: bmCapabilities 0x07 sends break line coding and serial state get/set/clear comm features CDC Union: bMasterInterface 0 bSlaveInterface 1 Country Selection: iCountryCodeRelDate 4 04052004 wCountryCode 0x4803 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 96 bNumInterfaces 3 bConfigurationValue 2 iConfiguration 0 bmAttributes 0x80 (Bus Powered) MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 2 Communications bInterfaceSubClass 2 Abstract (modem) bInterfaceProtocol 1 AT-commands (v.25ter) iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 128 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 10 CDC Data bInterfaceSubClass 0 Unused bInterfaceProtocol 0 iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 10 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x02 EP 2 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 10 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 10 CDC Data bInterfaceSubClass 0 Unused bInterfaceProtocol 0 iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 1 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x03 EP 3 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 1 CDC Header: bcdCDC 1.10 CDC Call Management: bmCapabilities 0x03 call management use DataInterface bDataInterface 1 CDC ACM: bmCapabilities 0x07 sends break line coding and serial state get/set/clear comm features CDC Union: bMasterInterface 0 bSlaveInterface 1 Country Selection: iCountryCodeRelDate 4 04052004 wCountryCode 0x4803 Device Status: 0x0000 (Bus Powered) -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html