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Description of problem:
When attempting to remove the driver for an extant network card, hotplug's net.agent script automatically re-inserts the module if it is aliased to an interface in /etc/modprobe.conf
Even modules that are blacklisted (by hotplug) get loaded
This might be what is causing bug 173291

Version-Release number of selected component (if applicable):
hotplug-2004_09_23-7

How reproducible:
Always

Steps to Reproduce:
1.  add a driver for your net card in modprobe.conf (eg: alias eth0 e100)
2.  load the driver as normal (eg: ifup eth0)
3.  bring the interface down (eg: ifdown eth0)
4.  attempt to unload the driver (eg: rmmod e100)

  

Actual Results:  the module will automatically get re-inserted and the interface will be brought back up!

Expected Results:  rmmod should remove the module cleanly

Additional info:

I've tracked this down to hotplug's net.agent script.  When a network module is removed fron the system, net.agent attempts to bring down the associated interface (ifdown $INTERFACE).  But running ifdown on the interface causes modprobe to re-insert the module for that interface (before ifdown can bring it down).
  
To make matters worse, hotplug then detects that modprobe has inserted a new network card and runs itself with an "add" -- thereby actually bringing the interface up as you were trying to remove it entirely.