Recently I switched from windows to Macbook which is my first time to use the MacOS. It is fresh to me like the feeling when I start to use Linux OS. Well, I knew MacOS is unix-like OS, so it has the genie like Linux. I bought the Macbook M5 Pro with 2TB SSD and 48GB RAM. My intension is to use it to learn AI stuff, also I do need a personal laptop for my master studying. I have a very old laptop which is over 10 years. It is also the time to buy a new laptop. Although most of time I am using company’s laptop to process some personal topics.
I am thinking how to use it to do potential development and investigation. The major requirement from me is about Linux and QNX development and study. For Linux development, my major purpose is about kernel compiling and simulation by the qemu. I had some introduction before[1] [2] to setup the qemu environment for the google android kernel project, combine with a busybox I can lunch a tiny linux with android kernel, which makes me possible to debug and study the android kernel. Google android kernel project is not just kernel, it also includes the complete toolchain and build environment such as Bazel. Unfortunately, Bazel is not supported well by MacOS. I have to install virtual machine. The best virtial machin is Orbstack in MacOS. I tried Docker but the corss compile efficiency is worse than Orbstack. As you know the biggest problem is M serials apple silicon is ARM based processor, we need a VM with better efficiency for the x86/amd64 simulation. Although the Orbstack still slower than the native Linux machine, but it is acceptable. I tried google project android14-6.1 branch. It can be built successfully.
But the android16-6.12 branch can not be built. I see there is a ticket reported to Orbstack some months ago. The issue is not sovled yet. So to build the android kernel v6.12 I tried to build it manually which w/o the Bazel environment.
Fetch the code:
git clone --branch android16-6.12-lts --single-branch --depth 1 https://android.googlesource.com/kernel/common
Setup build env: we can reuse the prebuilts folder from any branch of google android kernel project.
export PATH=$PATH:/Volumes/my1tb/test/prebuilts/clang/host/linux-x86/clang-r536225/bin/
export ARCH=arm64
export SUBARCH=arm64
export CLANG_TRIPLE=aarch64-linux-gnu-
Generate kernel configuration:
make O=out LLVM=1 gki_defconfig
Please note that after the .config is generated, we need to modify the out/.config to add any drivers we need and the initramfs to compile the busybox ramdisk into the kernel image.
Compile the kernel:
make O=out LLVM=1 -j4
Generate the Image:
llvm-objcopy -O binary -R .notes -R .comment -S vmlinux Image
Launch the Kernel with QEMU: simplest command
qemu-system-aarch64 -machine virt -cpu cortex-a57 -machine type=virt -m 1024 -smp 4 -kernel /Users/huang/workspace/android/Image2 --append "rdinit=/linuxrc root=/dev/vda rw console=ttyAMA0 loglevel=8" -nographic -accel hvf
