On Thu, Nov 17, 2016 at 10:14:34AM +0100, Wim Osterholt wrote: > > For completeness I should also try with SMP unset. That is for tomorrow > > then. > > With CONFIG_SMP unset nothing goes wrong here either. > It looks like it has been fixed in 4.9-rc5, but I should also double check > several conbinations on my (slower) laptop. Nov 17 15:07:49 localhost kernel: usb 4-1: new full-speed USB device number 2 using uhci_hcd Nov 17 15:07:49 localhost kernel: usb 4-1: New USB device found, idVendor=0572, idProduct=1340 Nov 17 15:07:49 localhost kernel: usb 4-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 Nov 17 15:07:49 localhost kernel: usb 4-1: Product: USB Modem Nov 17 15:07:49 localhost kernel: usb 4-1: Manufacturer: Conexant Nov 17 15:07:49 localhost kernel: usb 4-1: SerialNumber: 12345678 Nov 17 15:07:50 localhost mtp-probe[12956]: checking bus 4, device 2: "/sys/devices/pci0000:00/0000:00:1d.2/usb4/4-1" Nov 17 15:07:50 localhost mtp-probe[12956]: bus: 4, device: 2 was not an MTP device Nov 17 15:07:51 localhost kernel: Check point 1 Nov 17 15:07:51 localhost kernel: Check point 2 Nov 17 15:07:51 localhost kernel: Check point 3 Nov 17 15:07:51 localhost kernel: Check point 4 Nov 17 15:07:51 localhost kernel: Check point 5 Nov 17 15:07:51 localhost kernel: Check point 6 Nov 17 15:07:51 localhost kernel: Check point 7 Nov 17 15:07:51 localhost kernel: Check point 8 Nov 17 15:07:51 localhost kernel: Check point 9 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 ... You can get a few logs concatenated at http://webserver.djo.tudelft.nl/insane488.logs Usually the oops follows immediately after inserting the modem, but in one case it took a few seconds extra before the oops. I think that is the one that printed the full range of checkpoints. On another 3 machines running 4.9-rc5 here everything went fine on insertion. Switching back to 4.8.8 produced the bug with outputs similar to the above. Now back to the laptops to see if I can get confirmation of having seen the oops at 4.9-rc5 in some way. I'm not sure now. Regards, Wim. -- 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