I have been bisecting around the 3.13 and 3.14 kernel releases: The 3.13.11 fails, but far less often than the 3.13.0, and with a dmesg trace that indicates an attempt to trace a USB issue of this kind. See dmesg_3_13_7: [ 20.158116] ------------[ cut here ]------------ [ 20.158126] WARNING: CPU: 0 PID: 0 at /home/apw/COD/linux/drivers/usb/host/xhci-ring.c:1572 handle_cmd_completion+0x35e/0x3c0() [ 20.158128] Modules linked in: ctr ccm uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core usbmouse bnep rfcomm videodev joydev ath3k btusb bluetooth snd_hda_ [ 20.158198] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.13.7-031307-generic #201403240156 [ 20.158200] Hardware name: LENOVO 80EU/Lenovo B50-70, BIOS 9DCN29WW(V2.09) 11/21/2014 [ 20.158201] 00000000 00000000 f2c0bea4 c166f493 c18f2580 f2c0bed4 c1058ee4 c186e724 [ 20.158207] 00000000 00000000 c18f2580 00000624 c14f04be c14f04be f2daa000 f25d3640 [ 20.158213] 00000018 f2c0bee4 c1058f22 00000009 00000000 f2c0bf28 c14f04be f27e18ac [ 20.158218] Call Trace: [ 20.158225] [<c166f493>] dump_stack+0x41/0x52 ... It is becoming more and more difficult to bisect.
3.14.0 seems the first release solving the issue (OK on 21 tries, to be confirmed). So I will simply stick on ppa 3.14-trusty until the next LTS, or upgrade to utopic or vivid. ** Attachment added: "dmesg_3.13.7" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1476783/+attachment/4437661/+files/dmesg_3.13.7 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1476783 Title: Lenovo B5970 USB peripherals are not detected To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1476783/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
