> The proposed patch adds the x86_64 micro-architecture feature levels v2 / v3 / v4 as new Kconfig options if wanting to cater to them when building the kernel with modern GCC and LLVM Clang compilers. It's just some Kconfig logic to then set the "-march=x86-64-v4" or similar compiler options for the kernel build.

How much would these compiler flags save a standard datacenter and then an HPV center?

I like the sound of AMD engineer Borislav Petkov, him & I could fix the world together }:-8)