On Wed, Feb 04, 2026 at 05:55:16PM -0800, Jakub Kicinski wrote:

On Wed, 4 Feb 2026 06:51:46 +0100 Thomas Weißschuh wrote:

quoted

quoted

make -j16 O="$kobj" INSTALL_HDR_PATH="${kobj}/hdr" headers_install
popd

pushd uapi
find . -type f -name '*.h' -exec cp -v "${kobj}/hdr/include/{}" {} \;  

Here only those headers which already exist in ethtool's uapi/ directory
are copied. As linux/typelimits.h is new, it is now missing.
Honestly, if a user fiddles with the internals of the UAPI headers like
this, it is on them to update their code if the internal structure
changes. In your case a simple 'touch uapi/linux/typelimits.h'
before running the script will be enough. Also internal.h now requires
an explicit inclusion of <limits.h>, as that is not satisfied by the
UAPI anymore.

Hopefully you understand that while due to uapi header copy this is not
a huge issue for ethtool itself, but it is a proof that your changes
can break normal user space applications which do not vendor in uapi.

A regular application which uses a full UAPI headers tree will get
access to the new header automatically.
If the application uses symbols from <limits.h> without including <limits.h>
on its own, it is broken.


Thomas