# no /dev/loop* (loop module loaded...) [SOLVED]

## acreal

Hi,

well, title says it all, i'm using kernel 2.6.13-gentoo-5 on amd64, udev 0.70 and doing as follows gives me an error:

# zgrep LOOP /proc/config.gz

CONFIG_BLK_DEV_LOOP=m

...

# modprobe loop

# lsmod

Module                  Size  Used by

loop                   13648  0

...

# mount -o loop file.iso /mnt/point

mount: could not find any device /dev/loop#

# dmesg

...

loop: loaded (max 8 devices)

I saw many post about this (gentoo or not related), but they all end up like "oops, sorry, if thought i had loop device support in my kernel". This is my first time using udev, so i assume this may be related. No clue really.

TIA

vincentLast edited by acreal on Sat Nov 12, 2005 10:20 pm; edited 1 time in total

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## dsd

does running "udevstart" after loading the driver make the nodes appear?

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## acreal

Yes, thanks a lot. Too bad udev does not handle this, though i assume there is no proper way for the kernel (maybe udev could watch sysfs ?) to notify userspace. Anyway, thx again.

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## dsd

it does handle this automatically. you need to enable CONFIG_HOTPLUG in your kernel config.

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## dwaynemac

i'm trying to install loop module so i run "modprobe loop" and here's my output 

```
FATAL: Module loop not found.

```

how do i get the module?

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## acreal

 *Quote:*   

> it does handle this automatically. you need to enable CONFIG_HOTPLUG in your kernel config

 

hm actually i couldn't set hotplug support at install (did not search really), so i just went the "who cares ?" way  :Wink:  thx again for the hint.

 *Quote:*   

> how do i get the module ?

 

It is a kernel module. You must compile it. Download the latest sources from portage, then

# cd /usr/src/linux-x-y-z-gentoo-a

# zcat /proc/config.gz >.config

# make oldconfig

# make menuconfig -> here go choose loop support under FS

# make all modules_install

# cp arch/YOUR_ARCH/boot/bzImage /boot (you may need to mount /boot if it is on a separate partition)

Then add an entry for the new kernel in /boot/grub/menu.lst, reboot and

# modprobe loop

------

Or just choose loop support from your actual kernel source tree and

# make modules modules_install

# depmod -a

# modprobe loop

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## dsd

 *acreal wrote:*   

> hm actually i couldn't set hotplug support at install (did not search really), so i just went the "who cares ?" way  thx again for the hint.

 

its on by default so you must have turned it off. to search for it, type /HOTPLUG<enter> in menuconfig.

you should probably turn it on as you'll need it in other situations too. for example, if you plug in a usb hard disk, you won't get the /dev/sda1 partitions being created unless udev is notified about the new device via the hotplug system.

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## acreal

Yeah, i sure need it, but didn't had the time to search at the time. Although i think the requirements to unlock items are listed in the <Help> option ?

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## acreal

Just noticed it was configured in the source tree aleardy but not compiled in, must have changed that and not recompiled...

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