Re: compat kernel modules and GENERIC

[Andrew Doran <ad%netbsd.org@localhost>]

On Tue, Mar 17, 2009 at 09:42:15AM +1100, matthew green wrote:

> the right long term
> fix is to make "compat" module work for COMPAT_50 things in
> a current "GENERIC" configuration.  the majority of the work
> to do that is to simple *take out* "#ifdef COMPAT_50"
> conditionals from standard kernel code.  that leaves the
> systems in place that "compat" module needs.

There are concerns about that approach. Presumably there are nutjobs that
want to have kernels absolutely free from the imperfections of the past. In
addition there are cases where a facility has enough overhead to justify
modularizing it. In some cases hooking code/data in at runtime with low
overhead, at random points in the kernel, and without bugs, is very tricky.