On a Lenovo x3650 M5 server running Ubuntu 14.04 GA, mapping of USB flash drives to USB2 or USB3 busses is irregular. For instance, with two USB3 ADATA USB flash drives plugged into the system, one on an external port that's marked with the blue USB3 color and the other marked as USB2, lsusb shows:
ubuntu@oil-drapion:~$ lsusb
Bus 004 Device 002: ID 8087:8002 Intel Corp.
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:800a Intel Corp.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 04b4:6570 Cypress Semiconductor Corp.
Bus 001 Device 007: ID 125f:312b A-DATA Technology Co., Ltd. Superior S102 Pro
Bus 001 Device 006: ID 125f:312b A-DATA Technology Co., Ltd. Superior S102 Pro
Bus 001 Device 005: ID 04b4:6570 Cypress Semiconductor Corp.
Bus 001 Device 008: ID 04b3:4010 IBM Corp.
Bus 001 Device 002: ID 0624:0248 Avocent Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Despite having different external USB port markings, both appear to be on USB bus 1, which is USB2.
Moving one device to another USB3 port shows it as being on the USB3 bus (bus 2). Initially we thought the external markings were just wrong; however....
Re-installing the OS (via MAAS), while NOT moving the USB drives, causes the problem to reappear:
ubuntu@oil-drapion:~$ lsusb
Bus 002 Device 002: ID 8087:8002 Intel Corp.
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:800a Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 004: ID 04b4:6570 Cypress Semiconductor Corp.
Bus 003 Device 003: ID 125f:312b A-DATA Technology Co., Ltd. Superior S102 Pro
Bus 003 Device 006: ID 04b4:6570 Cypress Semiconductor Corp.
Bus 003 Device 005: ID 125f:312b A-DATA Technology Co., Ltd. Superior S102 Pro
Bus 003 Device 007: ID 04b3:4010 IBM Corp.
Bus 003 Device 002: ID 0624:0248 Avocent Corp.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Again, both drives appear on the same USB2 bus (3 in this case).
I was unable to reproduce the problem on another system (an Intel NUC). My ability to test is somewhat limited because the system is in 1SS, so I'm reliant on Canonical IS to swap USB drives.
I'm attaching output from "sudo lsusb -v", "sudo lshw", and "dmesg" on the affected system to this bug report.
ubuntu@oil-drapion:~$ lsb_release -rd
Description: Ubuntu 14.04 LTS
Release: 14.04
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1593291
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.