out of tree kernel modules (was: compiling modules and FDT define)

[Warner Losh]

> On Aug 7, 2016, at 4:13 PM, Bernd Walter <ticso at cicely7.cicely.de> wrote:
> 
> On Fri, Aug 05, 2016 at 08:20:11PM -0700, Adrian Chadd wrote:
>> Hi,
>> 
>> Try adding opt_platform.h to SRCS in the module makefile?
>> 
>> You don't need to add it to the tree. You just have to setup your path
>> to point things /at/ a kernel build tree withall the opt_xxx.h in
>> them.
>> 
>> here's what I do:
>> 
>> #!/bin/sh
>> 
>> X_SRCDIR=${X_SRCDIR:="/home/adrian/work/freebsd/head/src/"}
>> X_KERNDIR=${X_KERNDIR:="/home/adrian/work/freebsd/head/obj/usr/home/adrian/work/freebsd/head/src/sys/GERTRUDE/"}
>> X_KMODOWN=${X_KMODOWN:="adrian"}
>> X_KMODGRP=${X_KMODGRP:="adrian"}
>> 
>> # This allows for -HEAD includes for net80211 ..
>> env CFLAGS="-I../../../sys/" \
>> make \
>>    MODULES_OVERRIDE="" \
>>    DEBUG_FLAGS="-g" \
>>    DEBUG_FLAGS="-g" \
>>    KMODDIR="/home/adrian/git/github/erikarn/athp/otus/freebsd/modules/" \
>>    KMODOWN="${X_KMODOWN}" \
>>    KMODGRP="${X_KMODGRP}" \
>>    MAKESYSPATH="${X_SRCDIR}/share/mk" \
>>    SYSDIR="${X_SRCDIR}/sys/" \
>>    KERNBUILDDIR="${X_KERNDIR}" \
>>    KERN_DEBUGDIR="" \
>>    $@
>> 
>> That gets me all the bits I need to be able to run make in module
>> directories and get the correct includes/links setup.
> 
> Oh damn - it used to be much easier than that.
> I'm still used to "make all install" for out of tree kernel modules.
> How is it handled for the few kmods in ports?

Mostly by setting KERNBUILDDIR correctly. If we have to jump through all these hoops too,
then I’ll take a look at fixing things…. The above looks more complex than should be
required.

Warner