can't access USB disk now and then

eteck · 10-03-2010, 07:01 PM

Every now and then my USB disk drops out and I get the following errors in dmesg
[247288.114545] EXT3-fs error (device sdb1): ext3_find_entry: reading directory #2 offset 0

But when I unplug it, and plug it back in do dmesg | tail, it doesn't pick it or any other usb storage device up (nothing comes out of dmesg this time).

So I tried to reload the module:
eteck@naavi:~$ sudo lsmod | grep usb
usbhid 36110 0
hid 67032 1 usbhid
usb_storage 39425 1

eteck@naavi:~$ sudo rmmod -f usb_storage
ERROR: Removing 'usb_storage': Resource temporarily unavailable

But as you can see I get the above error message.

They only think that works is a computer reboot (YUK!).

Any ideas:
* how to determine who is using it?
* force remove it
* solve my main issue of usb dropping out.

ciotog · 10-04-2010, 01:50 PM

The "lsof" command can be used to see who is using a file, so depending on your configuration you might be able to run something like:

Code:

lsof /dev/sdb1

Then you can end whatever processes are listed, and then maybe it will revive the USB stack.

I've used the following in the past when doing some USB work on a development platform: http://www.clearchain.com/blog/posts...us-under-linux

It works fairly well, but doesn't recover from all conditions of course.

The main issue might be something in a kernel module, or the device. It would require a lot more analysis to work it all out.