How to compile only changed files when building the kernel?

Question

linux

To install an old version of VirtualBox, you need to build the 5.4.xx kernel. I assembled it (I forgot to add support for Intel HD Audio beforehand). VirtualBox worked, only there was no sound on the laptop. Well, I think, now I will connect support in the form of a module and quickly rebuild it. But then a bummer awaited. In my opinion, after enabling the module, judging by the output of make, the kernel began to build again. Further, without changing anything, I launch the assembly and again it takes a long time. A clean build takes 52 minutes, and a rebuild (no changes) takes 52 minutes too! Having vast experience in assembling software for a variety of operating systems and devices, I know that only changed files are compiled during reassembly. I bet I'm doing something wrong.

fakeroot make-kpkg -j 3 --initrd --append-to-version=-custom kernel_image kernel_headers

PS: Linux last compiled 2.6 or 3.xx, maybe something has changed.

Answer 1

try instead of your command

make -j3 bindeb-pkg LOCALVERSION=-custom KDEB_PKGVERSION=$(make kernelversion)

Previously at least it worked
UPD: in 4.9.x it worked

Answer 2

The kernel itself only supports rebuilding changed files/options, but make-kpkg rebuilds the kernel clean.