17.1.3.1.2. Linux kernel min config

linux_config/min contains minimal tweaks required to boot gem5 or for using our slightly different QEMU command line options than Buildroot on all archs.

It is one of the default config fragments we use, as explained at: Section 17.1.3, “About our Linux kernel configs”>.

Having the same config working for both QEMU and gem5 (oh, the hours of bisection) means that you can deal with functional matters in QEMU, which runs much faster, and switch to gem5 only for performance issues.

We can build just with min on top of the base config with:

./build-linux \
  --arch aarch64 \
  --config-fragment linux_config/min \
  --custom-config-file linux_config/buildroot-aarch64 \
  --linux-build-id min \
;

vmlinux had a very similar size to the default. It seems that linux_config/buildroot-aarch64 contains or implies most linux_config/default options already? TODO: that seems odd, really?

Tested on 649d06d6758cefd080d04dc47fd6a5a26a620874 + 1.