Questions[dkms](ubuntu)

I have a kernel module that was registered with dkms. When a recent upgrade bumped my kernel to 4.15.0-50 I started getting the below error from dkms. Apparently kernel 4.15.0-50 was compiled with gcc version 7.3.0, but part of the upgrade involved installing a new version of gcc (7.4.0), which is causing dkms to fail. gcc 7.3 is no longer available on my system. How do I install gcc 7.3 in addition to 7.4, or even downgrade 7.4 to 7.3?

DKMS make.log for nvidia-430.14 for kernel 4.15.0-50-generic (x86_64)
Tue May 14 17:08:12 CDT 2019
make[1]: Entering directory '/usr/src/linux-headers-4.15.0-50-generic'
Makefile:976: "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel"
  SYMLINK /var/lib/dkms/nvidia/430.14/build/nvidia/nv-kernel.o
  SYMLINK /var/lib/dkms/nvidia/430.14/build/nvidia-modeset/nv-modeset-kernel.o

Compiler version check failed:

The major and minor number of the compiler used to
compile the kernel:

gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)

does not match the compiler used here:

cc (Ubuntu 7.4.0-1ubuntu1~18.04) 7.4.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


It is recommended to set the CC environment variable
to the compiler that was used to compile the kernel.

The compiler version check can be disabled by setting
the IGNORE_CC_MISMATCH environment variable to "1".
However, mixing compiler versions between the kernel
and kernel modules can result in subtle bugs that are
difficult to diagnose.

*** Failed CC version check. Bailing out! ***

/var/lib/dkms/nvidia/430.14/build/Kbuild:182: recipe for target 'cc_version_check' failed
make[2]: *** [cc_version_check] Error 1
make[2]: *** Waiting for unfinished jobs....
Makefile:1552: recipe for target '_module_/var/lib/dkms/nvidia/430.14/build' failed
make[1]: *** [_module_/var/lib/dkms/nvidia/430.14/build] Error 2
make[1]: Leaving directory '/usr/src/linux-headers-4.15.0-50-generic'
Makefile:81: recipe for target 'modules' failed
make: *** [modules] Error 2

Since last 4 days, I am trying to install amdgpu pro drivers on my ubuntu system and I am getting error.

1. I have downloaded drivers from here for Rx580.

2. I am following installation instructions from here.

3. First-time installation, I am getting dkms command not found.

4. executing below command will show me to install dkms

   dkms status

5. Installing dkms using below command

   sudo apt-get install dkms

6. Then try to install using below command, and getting error below is the screenshot for the same.

   ./amdgpu-pro-install -y

7. I have also tried on kernel 4.4 & 4.8 & 4.16 (getting above error on all kernels)

Below is my system configuration

Motherboard

Noob question here.... I read about modprobe and dkms and it seems to me they do the same thing, so what is the difference?

I've seen a few mentions about DKMS recently but it's not clear what it's actually doing on my system.

What does DKMS actually do and how do I use it?

During a recent apt-get dist-upgrade of 12.10 I received the following error:

Setting up linux-headers-3.5.0-19-generic (3.5.0-19.30) ...
Examining /etc/kernel/header_postinst.d.
run-parts: executing /etc/kernel/header_postinst.d/dkms 3.5.0-19-generic /boot/vmlinuz-3.5.0-19-generic
Error! Could not locate dkms.conf file.
File:  does not exist.

Any ideas?