[CLUE-Tech] module loading question

[Jed S. Baer]

On Wed, 26 Mar 2003 08:43:56 -0700
David Anselmi <anselmi at americanisp.net> wrote:

> Jeremiah Stanley wrote:
> >>  below ip_conntrack ip_conntrack_ftp
> > 
> > When I do that I get this error:
> > 
> > [root at duchamp root]# modprobe ip_conntrack
> > modprobe: Too deep recursion in module dependencies!
> > modprobe: Circular dependency? ip_conntrack_ftp ip_conntrack
> > Aborted
> 
> Actually, what you want is "above", not "below".  You could also use 
> post-install.  You want the ftp module loaded after ip_conntrack, below 
> loads it before (earlier in the stack, or towards the bottom of lsmod's 
> output).

Nothing like the facts to confuse an issue. ;-)

What I mean is, that doesn't jive with my experience. Re-reading the
modules.conf manpage, I completely agree. But, I'm having a hard time
reconciling that with what worked on my system.

When I was getting the USB serial thing to work, 'modprobe belkin_sa'
should have been all I needed to do, as the other modules should get
loaded based on /lib/modules/{kernel-version}/modules.dep file (that's my
understanding, anyway). But whatever process (declarations?) is required
for modules.dep to get built correctly wasn't occuring for the USB
modules. So, a little experimentation with modprobe revealed the sequence
of module loading was usbcore, usb-uchi, usbserial, belkin_sa. Any other
sequence, and the serial line wouldn't work.

So, by the book, this puts usbcore "below" usb-uhci, etc. Yet, these are
the lines in my modules.conf which produce a working USB serial line:

  above usb-uhci usbcore
  above usbserial usb-uhci
  above belkin_sa usbserial

It seems backwards, and I can't explain it in light of seeing the module
dependencies as a bottom-up stack. The only reason I can think of as to
why I used "above" is that it resembles the CLI process for loading
modules:

  $ modprobe usbcore
  $ modprobe usb-uhci
  ...

Where visually, the dependency is "above" the dependent. Makes no sense,
eh?

Of course, having upgraded the kernel in the mean time, I might or might
not be able to reproduce the situation. I haven't messed with the USB
stuff yet.

jed
-- 
I wouldn't even think about bribing a rottweiler with a steak that
didn't weigh more than I do. -- Jason Earl