Bad usb connection resets Xorg

[Patrick Den]

A bad usb connection seems to reset Xorg. Ubuntu returns to the login screen.

First I had lots of cheap usb cables and cheap usb devices and usb-hubs under usb-hubs. Ubuntu became very unstable also Windows reported many times that an usb device was disconnected and connected again.
Now I have added adapters to some usb hubs. I have better cables, and I added ferrite noise-blockers. I also removed all unused usb devices. Only my Wacom Volito2 pen-tablet keeps causing problems, probably due to its bad hardware design (it works with 5.0V, but not with 4,95V).

If there is a problem with the communication with an usb device, Ubuntu returns directly to the inlog screen, and any open editor loses everything that was not saved before.
Ubuntu doesn't even write something in a log file.
If the communication with an usb device is already wrong during startup, the inlog screen is not shown, but a text-mode login is shown.

I report this error, because of the basic problem. A problem outside the computer should not be the cause of losing my work in a text-editor.

This problem occurred also with Ubuntu 10.04. I don't know if I had this before that.

Ubuntu 10.10, 64-bit
Gigabyte GA-EP45T-UD3R motherboard.

[Patrick Den (pat31)]

I made a fresh install of Ubuntu 10.10 on the same computer. That also causes my session to restart with bad usb communication.

Other distributions don't reset the session with bad usb communication.
For example OpenSUSE 11.3 shows errors in the log files, but the session is not reset:
Dec 16 21:56:22 kernel: [ 814.553021] usb 5-2: device descriptor read/64, error -71
Dec 16 21:56:22 kernel: [ 814.767022] usb 5-2: device descriptor read/64, error -71
Dec 16 21:56:22 kernel: [ 815.083021] usb 5-2: device descriptor read/64, error -71
Dec 16 21:56:23 kernel: [ 815.297024] usb 5-2: device descriptor read/64, error -71
Dec 16 21:56:23 kernel: [ 815.908027] usb 5-2: device not accepting address 11, error -71
Dec 16 21:56:24 kernel: [ 816.418028] usb 5-2: device not accepting address 12, error -71
Dec 16 21:56:24 kernel: [ 816.418036] hub 5-0:1.0: unable to enumerate USB device on port 2

I also tried the LiveCD of Ubuntu 11.04 alpha1. That one is also okay. The session is not restarted.

Perhaps the problem is solved in the new Ubuntu.

[Patrick Den (pat31)]

In Ubuntu 11.04 this problem no longer exists.
Please close this bug.

[Tormod Volden (tormodvolden)]

Thanks. Closing as requested by original submitter.