Re: kerneld behaviour

Bjorn Ekwall (
Fri, 5 Apr 1996 14:06:18 +0200 (MET DST)

You wrote:
> Dear all,
> I am new to the kerneld stuff and wonder if the modules loaded by
> kerneld automatically can be changed. Eg, can I ask kerneld to load
> bsd_comp.o instead of pppd.o when I issue the command pppd? Or
> loading both sbpcd.o and isofs.o if I type mount -t iso9660 /dev/xxxx
> /cdrom? Or is it really to do with depmod?
> I am using kernel 1.3.80 and modules-1.3.69.

The kernel requests via kerneld are symbolic (e.g. "char-major-97")
so that the decision of what module to load can be made in user-space.

The "tool" to use for this is "/etc/conf.modules", which is used
by modprobe to select the right module.
In order to use the bsd_comp module you just have to add these lines
to /etc/conf.module:

alias tty-ldisc-3 bsd_comp
alias ppp0 bsd_comp
alias ppp1 bsd_comp

If you have run "depmod -a", you will have a dependency file, which
for you kernel release will be called "/lib/modules/1.3.80/modules.dep".
This file is used by modprobe to find out that before it can load
the bsd_comp module, it has to load the slhc and ppp modules first.

To enable automatic loading of the sbpcd module, you will have to ensure
that modprobe knows that (according to linux/Documentation/devices.txt)
the sbpcd driver is accessed as a block device with major number 25.
This knowledge is sent to modprobe by adding this line to /etc/conf.modules:

alias block-major-25 sbpcd

That's it!

There is a very nice kerneld mini-HOWTO, written by Henrik Storner,
that you can find via my web-page.


Bjorn <> <>