Re: HEADSUP: drm-current-kmod now installs sources

On Wed, Aug 14, 2019 at 1:04 PM Ian Lepore <ian_at_freebsd.org> wrote:
>
> On Wed, 2019-08-14 at 19:55 +0200, Niclas Zeising wrote:
> > On 2019-08-14 19:23, Emmanuel Vadot wrote:
> > > On Wed, 14 Aug 2019 10:13:48 -0700
> > > John Baldwin <jhb_at_FreeBSD.org> wrote:
> > >
> > > > On 8/14/19 9:22 AM, Ian Lepore wrote:
> > > > > This all sounds vaguely wrong, backwards, to me.  A developer
> > > > > who is
> > > > > using a given module on their build system might want that
> > > > > module to be
> > > > > rebuilt automatically, but only if the build parameters match
> > > > > those of
> > > > > the running build host system.
> > > > >
> > > > > If my build host is running freebsd 12 amd64 and I'm doing a
> > > > > build for
> > > > > freebsd 13 armv7, I have no interest in automatic rebuilds of
> > > > > an amd64
> > > > > driver module for a different OS arch and version just because
> > > > > that
> > > > > module happens to be installed on the system I use to do
> > > > > crossbuilds.
> > > > >
> > > > > My objections are theoretical... this automation just seems
> > > > > improperly
> > > > > designed to me.  But it won't actually affect me in any way,
> > > > > because I
> > > > > don't build video driver modules from ports, and I don't run
> > > > > freebsd
> > > > > current on my build host machine.  Probably the number of
> > > > > people doing
> > > > > crossbuilding is small enough that nobody else is going to
> > > > > object to
> > > > > this "the whole world is amd64" automation.
> > > >
> > > > You assume DRM is amd64-only when it is definitely not.  It also
> > > > has
> > > > suitable guards in its Makefile to only build the relevant kernel
> > > > modules on supported architectures.
> > >
> > >   I clearly don't want to spend time to build the drm and radeon
> > > modules
> > > when I'm hacking on arm64.
> > >   Shouldn't LOCAL_MODULE have ${TARGET}.${TARGET_ARCH} as a
> > > subdirectory ? So when you install drm-kmod-* it will only install
> > > the
> > > source in /usr/local/modules/${TARGET}.${TARGET_ARCH}/ ? (or
> > > whatever
> > > the correct dir is).
> > >
> >
> > I'm not sure what you're trying to accomplish.  I might be
> > misunderstanding completely, but, at least the drm ports have
> > safeguards
> > in their makefiles so they'll only be built for those arches where
> > there
> > is support, and only the modules needed, as an example, i915kms.ko
> > will
> > only be built on amd64 and i386, if that's what you're worried about.
> > Regards
>
> I can't understand what you guys are not-understanding.  New machinery
> has been added that says "if some module source code exists in this
> absolute fixed location on the build machine, then whenever you do any
> kernel build for any OS version or any arch, rebuild that module source
> code so that the the build machine's video drivers stay in sync with
> the build machine's kernel."

LOCAL_MODULES="" does seem like a sensible default when we're not
building a native kernel.