Comment # 14 on bug 1177250 from Takashi Iwai

Now I took a deeper look, and found that it's a packaging problem in rtl8812au.

Although rtl8122.spec tries to replace KSRC, it failed because now Makefile
assigns it in a different way.  So KSRC was left unmodified, pointing to the
default running kernel, which is the kernel-default.  That is,
rtl8812au-kmp-preempt was built against kernel-default and it contains the
modules for kernel-default!  That explains the whole strange errors and
behavior.

As a fix, you'd need to pass KSRC=... in the command line argument for make
instead of replacing it in Makefile.

Reassigned to the package maintainer.