Building Falco - linux-on-ibm-z/docs GitHub Wiki

Building Falco

The instructions provided below specify the steps to build Falco version 0.44.1 on Linux on IBM Z for following distributions:

  • RHEL (8.10, 9.6, 9.8, 10.1, 10.2)
  • SLES 15 SP7
  • Ubuntu (22.04, 24.04)

Falco supports two kernel drivers starting with 0.34.x releases on s390x: Kernel module and Modern eBPF probe. Please check driver - kernel version support matrix for detailed information.

General Notes:

  • When following the steps below please use standard permission user unless otherwise specified.
  • A directory /<source_root>/ will be referred to in these instructions, this is a temporary writable directory anywhere you'd like to place it.

1. Build using script

If you want to build Falco using manual steps, go to step 2.

Use the following commands to build Falco using the build script. Please make sure you have wget installed.

wget https://raw.githubusercontent.com/linux-on-ibm-z/scripts/master/Falco/0.44.1/build_falco.sh

# Run bash build_falco.sh -h to see all available options
bash build_falco.sh

In case of error, check logs for more details or go to Step 2 to follow manual build steps.

2. Install dependencies

export SOURCE_ROOT=/<source_root>/
PATCH_URL="https://raw.githubusercontent.com/linux-on-ibm-z/scripts/master/Falco/0.44.1/patch"

2.1. Install Basic Dependencies

  • RHEL 8.10

    sudo yum install -y gcc-toolset-13-gcc gcc-toolset-13-gcc-c++ git make cmake autoconf automake pkg-config patch libtool elfutils-libelf-devel diffutils which createrepo libarchive wget curl rpm-build kmod kernel-devel-$(uname -r) perl-IPC-Cmd perl-bignum perl-core clang llvm bpftool

source /opt/rh/gcc-toolset-13/enable

  • RHEL 9.6

    sudo yum install -y openssl-devel libstdc++-static libstdc++-devel c-ares-devel gcc gcc-c++ git make cmake autoconf automake pkg-config patch perl-IPC-Cmd perl-bignum perl-core perl-FindBin libtool elfutils-libelf-devel diffutils which createrepo libarchive wget curl rpm-build kmod kernel-devel-$(uname -r) bpftool clang

  • RHEL 9.8

    sudo yum install -y openssl-devel libstdc++-static libstdc++-devel c-ares-devel gcc gcc-c++ git make cmake autoconf automake pkg-config patch perl-IPC-Cmd perl-bignum perl-core perl-FindBin libtool elfutils-libelf-devel diffutils which createrepo libarchive wget curl rpm-build kmod kernel-devel-$(uname -r) bpftool
sudo yum install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm
sudo yum install -y clang19
sudo alternatives --install /usr/bin/clang clang /usr/bin/clang-19 100 --slave /usr/bin/clang++ clang++ /usr/bin/clang++-19

  • RHEL (10.1, 10.2)

    sudo yum install -y openssl-devel libstdc++-static libstdc++-devel c-ares-devel gcc gcc-c++ git make cmake autoconf automake pkg-config patch perl-IPC-Cmd perl-bignum perl-core perl-FindBin libtool elfutils-libelf-devel diffutils which createrepo libarchive wget curl rpm-build kmod kernel-devel-$(uname -r) bpftool
sudo yum install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-10.noarch.rpm
sudo yum install -y clang19
sudo alternatives --install /usr/bin/clang clang /usr/bin/clang-19 100 --slave /usr/bin/clang++ clang++ /usr/bin/clang++-19

  • SLES 15 SP7

    SLES_KERNEL_VERSION=$(uname -r | sed 's/-default//')
SLES_KERNEL_PKG_VERSION=$(sudo zypper se -s 'kernel-default-devel' | grep ${SLES_KERNEL_VERSION} | head -n 1 | cut -d "|" -f 4 - | tr -d '[:space:]')
sudo zypper install -y gcc gcc-c++ gcc14 gcc14-c++ git-core cmake patch which automake autoconf libtool libelf-devel gawk tar curl vim wget pkg-config glibc-devel-static "kernel-default-devel=${SLES_KERNEL_PKG_VERSION}" kmod clang17 llvm17 bpftool

  • Ubuntu 22.04

    sudo apt-get update
sudo apt-get install -y git cmake libssl-dev build-essential pkg-config autoconf wget curl patch libssl-dev libelf-dev gcc rpm linux-headers-$(uname -r) linux-tools-$(uname -r) kmod clang llvm

  • Ubuntu 24.04

    sudo apt-get update
sudo apt-get install -y git cmake libssl-dev build-essential pkg-config autoconf wget curl patch libtool libelf-dev gcc gcc-13 g++-13 rpm linux-headers-$(uname -r) linux-tools-$(uname -r) kmod clang llvm

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-13 100 --slave /usr/bin/g++ g++ /usr/bin/g++-13
export CC=$(which gcc)
export CXX=$(which g++)

2.2. Install CMake 3.28.3 (Only for RHEL 8.10, RHEL 9.6, Ubuntu 22.04)

cd $SOURCE_ROOT
wget -q https://cmake.org/files/v3.28/cmake-3.28.3.tar.gz
tar -xf cmake-3.28.3.tar.gz
cd cmake-3.28.3
./bootstrap
make -j"$(nproc)"
sudo make install
export PATH=/usr/local/bin:$PATH
cmake --version

2.3. Install Go

cd $SOURCE_ROOT
export GO_VERSION="1.25.0"
wget -q https://go.dev/dl/go"${GO_VERSION}".linux-s390x.tar.gz
chmod ugo+r go"$GO_VERSION".linux-s390x.tar.gz
sudo tar -C /usr/local -xzf go"$GO_VERSION".linux-s390x.tar.gz
sudo ln -sf /usr/local/go/bin/go /usr/bin/
sudo ln -sf /usr/local/go/bin/gofmt /usr/bin/
export GOPATH=$SOURCE_ROOT
export PATH=$GOPATH/bin:$PATH
export CC=$(which gcc)
export CXX=$(which g++)
go version

2.4. Install bpftool (Only for Ubuntu 22.04)

cd $SOURCE_ROOT
git clone --depth 1 --recurse-submodules https://github.com/libbpf/bpftool.git
cd bpftool && cd src
CLANG=Nope make -j8
sudo make install

2.5. Build container plugin

cd $SOURCE_ROOT
git clone --depth 1 -b plugins/container/v0.7.1 https://github.com/falcosecurity/plugins.git
cd plugins/plugins/container
make libcontainer.so
tar zcf $SOURCE_ROOT/container-0.7.1-linux-s390x.tar.gz libcontainer.so

3. Build and Install

3.1. Download source

cd $SOURCE_ROOT
git clone --depth 1 -b 0.44.1 https://github.com/falcosecurity/falco.git
cd falco

3.2. Apply patches

  • To include container plugin built for s390x

    wget -O $SOURCE_ROOT/falco/cmake/modules/falcosecurity-libs-repo/libs_container_plugin_cmake.patch $PATCH_URL/libs_container_plugin_cmake.patch

sed -i "s#SOURCE_ROOT_PATH#$SOURCE_ROOT#g" $SOURCE_ROOT/falco/cmake/modules/falcosecurity-libs-repo/libs_container_plugin_cmake.patch

curl -sSL $PATCH_URL/falco.patch | git apply -

  • To turn off modern BPF support (only for RHEL 8.x)

    CMAKE_TEST_FLAG=" -DBUILD_FALCO_MODERN_BPF=OFF "

3.3. Configure

  • Setup build directory

    mkdir -p $SOURCE_ROOT/falco/build
cd $SOURCE_ROOT/falco/build

  • Setup unit tests

    CMAKE_TEST_FLAG+=" -DBUILD_FALCO_UNIT_TESTS=ON "   # Only when unit tests are expected to be run after building Falco

CMAKE_TEST_FLAG=""  # Only when unit tests are not needed

  • Setup common CMake flags (For RHEL and Ubuntu)

    CMAKE_FLAGS="-DFALCO_ETC_DIR=/etc/falco -DUSE_BUNDLED_DEPS=ON -DCMAKE_BUILD_TYPE=Release -DBUILD_DRIVER=ON ${CMAKE_TEST_FLAG}"

  • Setup common CMake flags (For SLES 15 SP7)

    CMAKE_FLAGS="-DFALCO_ETC_DIR=/etc/falco -DUSE_BUNDLED_DEPS=ON -DCMAKE_BUILD_TYPE=Release -DBUILD_DRIVER=OFF ${CMAKE_TEST_FLAG}"

  • Run CMake

    cmake $CMAKE_FLAGS ../

3.4. Build and Install

  • Build and install Falco

    cd $SOURCE_ROOT/falco/build
sed -i 's/!found/found/g' falcosecurity-libs-repo/falcosecurity-libs-prefix/src/falcosecurity-libs/userspace/libscap/engine/modern_bpf/scap_modern_bpf.c # Only for Ubuntu
make -j$(nproc)
sudo make install

  • Build kernel driver separately on SLES 15 SP7

    cd $SOURCE_ROOT/falco/build/
make driver \
    CC=/usr/bin/gcc-7 \
    CXX=/usr/bin/g++-7 \
    KERNELDIR=/lib/modules/$(uname -r)/build

4. Testing (optional)

cd $SOURCE_ROOT/falco/build
sudo ./unit_tests/falco_unit_tests

A separate Falco project https://github.com/falcosecurity/event-generator can be used to run further tests.

5. Validate installation (optional)

Note: Run sudo falco --help to see available options to run Falco. By default, Falco logs events to standard error.

5.1. Run Falco with Kernel module

  • Unload any existing module using

    sudo rmmod falco

  • Insert locally built version

    cd $SOURCE_ROOT/falco/build
sudo insmod driver/falco.ko

  • Run falco

    sudo LD_PRELOAD=/lib64/libresolv.so.2 falco -o engine.kind=kmod    # Only for RHEL 8.x
sudo falco -o engine.kind=kmod                                     # For rest

Output similar to following will be seen

Tue Jun 30 16:52:59 2026: Falco version: 0.44.1 (s390x)
Tue Jun 30 16:52:59 2026: Falco initialized with configuration files:
Tue Jun 30 16:52:59 2026:    /etc/falco/config.d/falco.container_plugin.yaml | schema validation: ok
Tue Jun 30 16:52:59 2026:    /etc/falco/falco.yaml | schema validation: ok
Tue Jun 30 16:52:59 2026: System info: Linux version 6.12.0-124.45.1.el10_1.s390x (mockbuild@2a6027cd43144619bdb7d180f6911d83) (gcc (GCC) 14.3.1 20250617 (Red Hat 14.3.1-2), GNU ld version 2.41-58.el10_1.2) #1 SMP Tue Mar 10 19:58:50 EDT 2026
Tue Jun 30 16:52:59 2026: Loaded plugin '[email protected]' from file /usr/share/falco/plugins/libcontainer.so
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'podman' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/podman/podman.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'docker' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/var/run/docker.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'cri' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/containerd/containerd.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/crio/crio.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/k3s/containerd/containerd.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/host-containerd/containerd.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'containerd' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: * enabled container runtime socket at '/run/host-containerd/containerd.sock'
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'lxc' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'libvirt_lxc' container engine.
Tue Jun 30 16:52:59 2026: [libs]: container: Enabled 'bpm' container engine.
Tue Jun 30 16:52:59 2026: Loading rules from:
Tue Jun 30 16:52:59 2026:    /etc/falco/falco_rules.yaml | schema validation: ok
Tue Jun 30 16:52:59 2026:    /etc/falco/falco_rules.local.yaml | schema validation: none
Tue Jun 30 16:52:59 2026: The chosen syscall buffer dimension is: 8388608 bytes (8 MBs)
Tue Jun 30 16:52:59 2026: Starting health webserver with threadiness 2, listening on 0.0.0.0:8765
Tue Jun 30 16:52:59 2026: Loaded event sources: syscall
Tue Jun 30 16:52:59 2026: Enabled event sources: syscall
Tue Jun 30 16:52:59 2026: Opening 'syscall' source with Kernel module
Tue Jun 30 16:52:59 2026: [libs]: Trying to open the right engine!

5.2. Run Falco with modern eBPF probe driver (default) (except RHEL 8.x)

sudo falco

Output similar to following will be seen

Tue Jun 30 16:54:42 2026: Falco version: 0.44.1 (s390x)
Tue Jun 30 16:54:42 2026: Falco initialized with configuration files:
Tue Jun 30 16:54:42 2026:    /etc/falco/config.d/falco.container_plugin.yaml | schema validation: ok
Tue Jun 30 16:54:42 2026:    /etc/falco/falco.yaml | schema validation: ok
Tue Jun 30 16:54:42 2026: System info: Linux version 6.12.0-124.45.1.el10_1.s390x (mockbuild@2a6027cd43144619bdb7d180f6911d83) (gcc (GCC) 14.3.1 20250617 (Red Hat 14.3.1-2), GNU ld version 2.41-58.el10_1.2) #1 SMP Tue Mar 10 19:58:50 EDT 2026
Tue Jun 30 16:54:42 2026: Loaded plugin '[email protected]' from file /usr/share/falco/plugins/libcontainer.so
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'podman' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/podman/podman.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'docker' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/var/run/docker.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'cri' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/containerd/containerd.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/crio/crio.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/k3s/containerd/containerd.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/host-containerd/containerd.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'containerd' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: * enabled container runtime socket at '/run/host-containerd/containerd.sock'
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'lxc' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'libvirt_lxc' container engine.
Tue Jun 30 16:54:42 2026: [libs]: container: Enabled 'bpm' container engine.
Tue Jun 30 16:54:42 2026: Loading rules from:
Tue Jun 30 16:54:42 2026:    /etc/falco/falco_rules.yaml | schema validation: ok
Tue Jun 30 16:54:42 2026:    /etc/falco/falco_rules.local.yaml | schema validation: none
Tue Jun 30 16:54:42 2026: The chosen syscall buffer dimension is: 8388608 bytes (8 MBs)
Tue Jun 30 16:54:42 2026: Starting health webserver with threadiness 2, listening on 0.0.0.0:8765
Tue Jun 30 16:54:42 2026: Loaded event sources: syscall
Tue Jun 30 16:54:42 2026: Enabled event sources: syscall
Tue Jun 30 16:54:42 2026: Opening 'syscall' source with modern BPF probe.
Tue Jun 30 16:54:42 2026: One ring buffer every '2' CPUs.
Tue Jun 30 16:54:42 2026: [libs]: Trying to open the right engine!

Reference: