[OE-core] [PATCH] kernel.bbclass: allow exporting files from kernel recipes to sysroot

[Mikko.Rapeli at bmw.de]

On Mon, Sep 24, 2018 at 02:38:36PM +0100, richard.purdie at linuxfoundation.org wrote:
> On Mon, 2018-09-24 at 13:20 +0000, Mikko.Rapeli at bmw.de wrote:
> > On Mon, Sep 24, 2018 at 02:11:13PM +0100, Richard Purdie wrote:
> > > On Mon, 2018-09-24 at 12:19 +0000, Mikko.Rapeli at bmw.de wrote:
> > > > > That was one old way, but not the only. And not for exposing
> > > > > non
> > > > > uapi
> > > > > headers.
> > > > 
> > > > What other ways exist?
> > > > 
> > > > I don't care how, but I must export custom kernel specific
> > > > headers
> > > > and
> > > > other files to other recipes in a build in ways which are
> > > > compatible
> > > > with
> > > > yocto upstream.
> > > > 
> > > > I have not seen any documented ways for this.
> > > 
> > > It may not be documented, perhaps because its actually very simple.
> > > 
> > > Any recipe can expose headers into the recipe sysroot, they simply
> > > install them where needed in do_install as normal.
> > > 
> > > So all you need is a recipe which installs the right headers and
> > > then
> > > you DEPEND on that recipe. Where that recipe gets the headers isn't
> > > relevant.
> > 
> > No, this does not work on sumo. My patch is needed for this to work.
> > 
> > Without my patch, users of kernel.bbclass have zero files in
> > tmp/sysroot-components even if they install extra files and extra
> > header only binary packages.
> > 
> > A generated image or SDK will have the files if the binary package is
> > installed but sysroot not.
> 
> I was replying from the perspective of how this should work in general.
> I agree that for this to work with a kernel recipe we do need the
> change that started this thread and that is probably a reasonable thing
> to do.

Good, then my patch is not going in the wrong direction.

Remaining problem is if file overwrites will be detected or not so that
accidental overrides of files in linux-libc-headers from kernel recipes
should not be possible...

-Mikko