Your Long Lived Driver - 440.31 will not build with the Linux 5.4.0-rc6 or -rc7 kernels. That is, it will not build with the kernel provided by Slackware from their -current/testing directory.
Several people have tried and they have all failed. The only who have succeeded are those who custom built their own kernels. Why? No one seems to know.
This has been discussed on the linuxquestions/slackware from in two different threads,
Any assistance would be greatly appreciated.
The problem has been solved.
Mr. Volkerding, the creator and maintainer of Slackware, has fixed the problem by rebuilding the kernel using,
Sat Nov 16 03:31:45 UTC 2019
CRYPTO_CRC32C_INTEL m -> y
Make modules before cleaning up the source tree. This does some magic in
Module.symvers that fixes building the NVIDIA kernel modules.