BPFroid Compilation error

[skandbug]

Following your documentation, I generated the docker image.
https://github.com/yanivagman/BPFroid
It is the following four steps:

1. Prepare compilation environment with docker: docker run -it --rm --privileged multiarch/qemu-user-static --credential yes --persistent yes
2. Use the Dockerfile in builder directory to build an image of the build environment
3. Run builder container with BPFroid sources mounted and kernel headers as well, e.g: docker run -it --rm -v /path/to/tracee:/tracee -v /path/to/android-kernel:/headers bpfroid_builder
4. Set KERN_HEADERS variable in the Makefile to point to the correct location, then make, e.g: KERN_HEADERS=/headers make

My Movements:

1. The third step I modified was: In the Makefile, I modified "#KERN_HEADERS := /home/yaniv/src/thesis/pixel3a/android-kernel/headers/kernel-headers" according to the original comment to "KERN_HEADERS:=/home/BPFroid/android-kernel/headers/kernel-headers"
2. Upload the bpfroid source code to the container's /home directory
3. Press step 4 to compile in the container. steps is:

• Make in the /home root directory. or use KERN_HEADERS=/headers make make

The following error is reported:

/home/BPFroid # make
fatal: not a git repository (or any of the parent directories): .git
test -d 3rdparty/libbpf/src || git submodule update --init || (echo "missing libbpf source" ; false)
fatal: not a git repository (or any of the parent directories): .git
missing libbpf source
make: *** [Makefile:66: 3rdparty/libbpf/src] Error 1


/home/BPFroid # KERN_HEADERS=/headers make
fatal: not a git repository (or any of the parent directories): .git
test -d 3rdparty/libbpf/src || git submodule update --init || (echo "missing libbpf source" ; false)
fatal: not a git repository (or any of the parent directories): .git
missing libbpf source
make: *** [Makefile:66: 3rdparty/libbpf/src] Error 1

I think there is a mistake in the steps of the operation, but I don't know which step is wrong.

Please answer.
Thanks!