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My syslog is constantly filled with messages like this:

Oct 16 11:48:35 my-laptop kernel: [61470.980078] hub 1-0:1.0: unable to enumerate USB device on port 2
Oct 16 11:48:35 my-laptop kernel: [61471.192079] hub 3-0:1.0: unable to enumerate USB device on port 2

The only USB device I use is Microsoft Natural Wireless Laser Mouse 7000. The laptop model is HP dv9500, Ubuntu 10.10, but the same was in the versions before.

How can I fix this?


Here's the output of sudo lsusb:

Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 003: ID 045e:071d Microsoft Corp. 
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

All USB devices seems to be working fine. I have some problems with DVD-R and sound card, but they are not USB.

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Does everything work correctly? (I'm especially thinking about internal devices that are sometimes connected to USB, like a webcam, touchpad, cardreader, ...) – JanC Oct 16 '10 at 16:59
What does sudo lsusb show for your system? – Kees Cook Oct 26 '10 at 19:01
I have updated the question with further information. – takeshin Oct 27 '10 at 15:08
up vote 3 down vote accepted

Looks like the kernel is just spitting out weird errors, unless your computer has a real usb device that is plugged in internally (such as webcam) which is being ignored, I think it's safe to say that the errors are erroneous.

Update: I found a computer which had the same issues, it was caused by a faulty usb port on the computer and it was confirmed to be the hardware since no matter what software was run on it it caused the same errors. This port caused all sorts of issues since a hp printer was plugged into it which needed firmware and the faulty usb port was corrupting the firmware sent to the printer causing it to start having issues with any machine it was plugged into.

You could report the bug back to the kernel team though:

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Definatly file a bug in launchpad using 'ubuntu-bug linux'. Those messages are not to be expected. – Andy Nov 17 '10 at 19:43

I had this problem with a Ubuntu 12.04 64-bit Live CD. It prevented all USB devices from working, which in my case was a wireless mouse and a wifi router. The hardware worked fine on the same machine in windows7 and with the 32-bit Ubuntu 12.04.

The fix was to enable IOMMU in the BIOS of my Gigabyte GA-990A-D3 motherboard. Everything works fine after that change.

This is problem is similar to a common one that people have trouble installing 64-bit Ubuntu because the keyboard does not work. If the keyboard uses a USB port it will have the symptom that it is a keyboard-specific problem, when it is actually a general USB failure.

Hopefully, this fix works for others with perhaps other hardware.

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