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I am using gentoo 2.6.30 and I tried to load a module as follows:

modprobe usbcore

with the response

modprobe: module 'usbcore' not found

However, I can find a directory with that name in the directory /sys/module/. What is wrong here?

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migrated from Feb 14 '13 at 19:05

This question came from our site for professional and enthusiast programmers.

If people think to close this question, answer it or give a reason to close it. Thank you. – Alex Feb 14 '13 at 17:23
This is not a question related to programming. Better to post on – Keith Feb 14 '13 at 17:27
Sure, I will try it there... – Alex Feb 14 '13 at 17:51
Which kernel version do you run? And which kernel version where the modules build for?(uname -a will show you the kernel version and the modules will be stored in /lib/modules/kernelversion/ ). – Hennes Feb 14 '13 at 19:13
locate usbcore.ko should tell you about files called that (really, which have that string in their name). My Fedora 18 system has no such module, BTW. The directory seems to be for the core of the USB system, not a module by itself. – vonbrand Feb 14 '13 at 19:30
up vote 0 down vote accepted

Modules that can be loaded live in /lib/modules/`uname -a`

If modprobe can not find it, the you forgot to install it. Either use a kernel with modules from a live CD or build the kernel along with the modules with genkernel.

Another possibility is that usbcore is already compiled into the kernel. I'm not sure about the correlation between /sys/modules/usbcore and whether it is present in the kernel or not.

Finally, loading usbcore alone is not enough. You will one of the uchi-, ochi-, echi-_hcd modules also. Loading things like usbhid for the input devices to work, goes without saying...

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if you already have the directory /sys/module/usbcore i would assume the module is already loaded. check if 'lsmod' or 'cat /proc/modules' are listing it, to be sure if its loaded or not.

one possible reason why modprobe might tell you it can't find the module, could be that its not indexed in /lib/modules/kernel version/modules.dep. you can regenerate this file by submitting 'depmod'.

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