Update README.md to note requirement for submodule initialization (#262)

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Co-authored-by: Alan Jowett <alanjo@microsoft.com>
1 file changed
tree: beb07a95f0a802e8cd41b0c0ecd6d4045c6c27f4
  1. .github/
  2. aarch64_test/
  3. bin/
  4. bpf/
  5. cmake/
  6. docs/
  7. external/
  8. scripts/
  9. test_framework/
  10. tests/
  11. ubpf/
  12. ubpf_plugin/
  13. vm/
  14. .clang-format
  15. .editorconfig
  16. .gitignore
  17. .gitmodules
  18. .travis.yml
  19. CMakeLists.txt
  20. Doxyfile
  21. LICENSE.txt
  22. mainpage.dox
  23. README.md
  24. requirements.txt


Userspace eBPF VM

Build Status Coverage Status


This project aims to create an Apache-licensed library for executing eBPF programs. The primary implementation of eBPF lives in the Linux kernel, but due to its GPL license it can't be used in many projects.

Linux documentation for the eBPF instruction set

Instruction set reference

API Documentation

This project includes an eBPF assembler, disassembler, interpreter (for all platforms), and JIT compiler (for x86-64 and Arm64 targets).

Checking Out

Before following any of the instructions below for building, testing, contributing, etc, please be sure to properly check out the source code which requires properly initializing submodules:

git submodule init
git submodule update --recursive

Building with CMake

Note: This works on Windows, Linux, and MacOS, provided the prerequisites are installed.

cmake -S . -B build -DUBPF_ENABLE_TESTS=true
cmake --build build --config Debug

Running the tests

Linux and MacOS

cmake --build build --target test --


ctest --test-dir build

Building with make (Linux)

Run make -C vm to build the VM. This produces a static library libubpf.a and a simple executable used by the testsuite. After building the library you can install using make -C vm install via either root or sudo.

Running the tests (Linux)

To run the tests, you first need to build the vm code then use nosetests to execute the tests. Note: The tests have some dependencies that need to be present. See the .travis.yml for details.

Before running the test (assuming Debian derived distro)

sudo apt-get update
sudo apt-get -y install python python-pip python-setuptools python-wheel python-nose
python2 -m pip install --upgrade "pip<21.0"
python2 -m pip install -r requirements.txt
python2 -m pip install cpp-coveralls

Running the test

make -C vm COVERAGE=1
nosetests -v   # run tests

After running the test

coveralls --gcov-options '\-lp' -i $PWD/vm/ubpf_vm.c -i $PWD/vm/ubpf_jit_x86_64.c -i $PWD/vm/ubpf_loader.c

Compiling C to eBPF

You'll need Clang 3.7.

clang-3.7 -O2 -target bpf -c prog.c -o prog.o

You can then pass the contents of prog.o to ubpf_load_elf, or to the stdin of the vm/test binary.


Please fork the project on GitHub and open a pull request. You can run all the tests with nosetests.


Copyright 2015, Big Switch Networks, Inc. Licensed under the Apache License, Version 2.0 <LICENSE.txt or http://www.apache.org/licenses/LICENSE-2.0>.