Running kernel 3.13.0-35-generic here. I was affected by the same issue. Using "echo -1 >/sys/module/usbcore/parameters/autosuspend" seemed to help a bit, although the reset entries "xHCI xhci_drop_endpoint called with disabled ep *******" were still there and system was blocking because of these continuous drops, leading to an unreliable (and incredibly slow) writing to the disk.
The best way to trigger the issue was for example to run an rsync reading from one partition on the external disk and writing to another partition on the same disk. Plugging the disk with an USB 2.0 cable would show no problems at all with same tests. After plugging the external disk to a an USB port on the back, I can confirm it works perfectly (and still in high speed mode, "new SuperSpeed USB device number 2 using xhci_hcd"). Upon inspection, I found that the USB 3.0 cable connecting the front USB ports to the motherboard was a bit loose at connecting the USB 3.0 part of it. USB 2.0 traffic would always work perfectly fine but problems would arise when estabilishing 3.0 links. So, long story short, please check other USB 3.0 ports and that those you are using are well connected. Although I was suspecting the PSU of the external disk (12V 1.5A) and a bug in the kernel (as I read here and elsewhere), in the end it was just a cable problem. Hope it helps. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1371233 Title: USB 3.0 connection is unreliable + xHCI xhci_drop_endpoint called with disabled ep To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1371233/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
