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I have a laptop running debian wheezy:

$ uname -a
Linux *pcname* 3.2.0-4-686-pae #1 SMP Debian 3.2.54-2 i686 GNU/Linux

I recently made a debian boot usb like so:

sudo dd if=debian-live-7.4-amd64-gnome-desktop.iso of=/dev/sdb

I remember the usb was not mounted during the dd but I think after it had finished writing, I tried mount -a just to see if I could view the files on the boot-usb. It didn't work (the mountpoint didn't show any files and I assumed it was not mounted) and later on I pulled out the usb while the computer was still turned on to go use the usb to install debian wheezy on another laptop.

Now whenever I turn on my laptop it spits the following error over and over:

[ 3221.396136] hub 4-0:1.0: unable to enumerate USB device on port 1
[ 3222.132073] usb 4-1: new full-speed USB device number 52 using ohci_hcd

this never used to happen.

I've done some googling and the other places I have seen mention this [bug?] discuss that it has occured after a kernel update. However I don't think I've even used apt since the other day when I pulled out the usb, so this can't be the problem for me.

I'm wondering whether the problem may be a lockfile which needs deleting or altering?

Feel free to request additional information and i can add it here. The issue manifests when no usb is plugged in. lsusb gives:

$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
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up vote 1 down vote accepted

It is a clear hw or deep kernel problem. The message is a kernel error message. Although there is some userspace component of the device detection (its name is udev), it can't give such messages.

When you this boot/install/live usbstick created, you didn't do anything which was able to cause a such hardware failure.

The bug reported on the mentioned link is about such problems, but probably not about your.

This error message only says, that the kernel can't find out, what kind of device are living on the first usb port.

My suggestion were to try some plug in/out, try another device in the same slot, or try this device in another usb slot, or on another machine. Finally you will be able to find out, what is broken.

I am sorry for the bad news, but the most probable cause of your problem is in such cases that the usb slot in your laptop is buggy or dead. But first you should try some plug in/out to test what is really gone.

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well i plugged in the same usb, rebooted, and now the error stops coming up... not really a fix i know, but its all good so i'll give you the tick :) – mulllhausen Apr 16 '14 at 12:15
the repeated error came back over the past few weeks sporadically. then the laptop started shutting down at random. i'm guessing it was a loose connection possibly tripping a safety circuit. the laptop was very old so i just threw it out. – mulllhausen May 11 '14 at 14:23
@mulllhausen I am sorry. It was probably a power problem with the USB soon. Sometimes it is only because a faulty power supply. – peterh May 12 '14 at 7:53

The reason may be in bad order of loading modules. Such error may raise in case uhci_hcd is loaded before ohci_hcd.

You can try following temporary workaround

 # sudo modprobe -vr uhci_hcd
 # sudo modprobe -va ohci_hcd
 # sudo modprobe -va uhci_hcd

If it works you should create /etc/modprobe.d/usb_hci_order.conf with following content

 # create a dependency on ohci for uhci, which fixes problems
 # with external usb devices not showing up
 softdep uhci_hcd pre: ohci_hcd

See Arch wiki and Arch BBS post

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