[Buildroot] [PATCH 2/3 v3] linux: add an option to install runtime headers

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Sun, 17 Jul 2016 14:50:38 +0200, Yann E. MORIN wrote:
> When the Linux kernel is patched with new externsions (e.g. aufs), it
> exposes new userland headers that were not necessarily available in the
> headers used to build the toolchain. Those headers will expose new
> features, like new filesystems internals.
> 
> Add an option for such packages to request the kernel installs its
> headers.
> 
> We do install those headers in a non-standard location, so that:
> 
>   - they do not override those provided by the toolchain;
> 
>   - they do not get inadvertently used.
> 
> Packages that really need those headers will have to add the correct -I
> path to their CPPFLAGS.
> 
> Note: this is not documented on-purpose, as we expect the set of
> packages that need that to be very limited. In which case, we'll
> notice they need those headers, and we can instruct the submitter
> to use these option and variable.
> 
> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

I have not applied this patch. Instead, I've tuned a bit the aufs-util
package so that we can directly use the headers from
$(LINUX_DIR)/include/uapi.

Thanks,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com