[QUOTE]In suse 12.3 (4.4.131-94.29-default), I downloaded the source package
(kernel-source-4.4.131-94.29.1.src.rpm), extract linux-4.4.tar.xz out
of it, copy to /usr/src/4.4.131-94.29 and update symbolic link from
/lib/modules/4.4.131-94.29-default/source to source →
Maybe the answer is in the other files, some patch that’s included with the distro source RPM. Or maybe that failing code branch hasn’t been ported and is only used in an isolated way? I haven’t had a closer look so far.
Have you checked the upstream kernel sources, to see if it compiles cleanly and then checking if your module compiles against it cleanly? Once you did, you can take it from there to the distro-specific things. If it already fails with the upstream code, the Linux kernel ML may be helpful to find out what needs to be adjusted.