Subject: Re: loading lkm's
To: Matthias Drochner <drochner@zelux6.zel.kfa-juelich.de>
From: Iain Hibbert <plunky@skate.demon.co.uk>
List: current-users
Date: 03/16/1997 12:00:37
On Sat, 15 Mar 1997, Matthias Drochner wrote:

> Excerpts from netbsd: 14-Mar-97 loading lkm's Iain Hibbert@skate.demon (845*)
> 
> > Hi, I'm just starting to write a device driver and am trying to hack out a
> > framework for it as an lkm so I can play without recompiling my kernel all
> > the time. 
> 
> I have such a framework for more than a year.

that might be a nice thing to have in the source tree, as an example of a
device driver lkm? at the moment, I have an empty device that loads and
unloads, with a postinstall script - I'm still working out how it should all
look, and it hasn't helped that there are no lkm devices in the NetBSD tree
(I found one in OpenBSD, and a couple in FreeBSD).

I'm still a bit concerned about some things though, because I get a panic now
and again.  I'm half convinced that its the union filesystem though (I never
get the panic when doing anything with the module/driver), I've always had a
bit of trouble with that, not sure why.  But I like it, and I'm not sure how
else to handle keeping my changes separate from the master source tree and
yet still being able to work on both easily.  Does anybody else use unionfs
extensively? 

> it is a great productivity increase for driver development.
> The framework itself is a loadable module at this time,
> but it requires some small kernel changes in the
> autoconfiguration part and in the bus driver the loadable
> drivers are attached to (I did this only for PCI and the busses
> where I made the drivers myself - VME and VIC.).
> If you are interested I'll explain in more detail.

yes that would be interesting, is it possible you could send me a tarfile of
your framework? 

iain