Morello Bootstrap Scripts

This page contains some simple instructions to get you started on Morello without using docker.
Requires: a Debian 11 based aarch64 or x86_64 environment with network access and this repository available inside.

Make sure you have around 4GB of available disk space for the whole process.

The scripts have not been tested in other environments, although any aarch64 based Linux might work.

Requirements: GIT 1.8.2 (for submodule branch support).

Setting up the build environment

$ apt install git build-essential python3

If cross compiling on x86 you also need:
$ apt install libtinfo5 linux-libc-dev-arm64-cross

Building

Quick build:

$ cd morello-sdk/morello
$ source ./env/morello-sdk
$ ./scripts/build-all.sh [options]

Which will perform a full cross build on aarch64 host. You can optionally pass --x86_64 to build-all.sh to do a cross-build from an x86_64 host.

$ ./scripts/build-all.sh --help

Usage: ./scripts/build-all.sh [options]

OPTIONS:
[ARCH]:
  --aarch64           build on an aarch64 host [DEFAULT]
  --x86_64            build on an x86_64 host

[MODULES]:
  --firmware          generate the firmware for Morello
  --linux             builds linux for Morello
  --kselftest         builds kselftest for Morello
  --c-apps            builds example c applications for Morello
  --rootfs            builds a busybox based rootfs for Morello

  --clean             cleans all the selected projects

  --help              this help message

On success, your binary is morello-sdk/morello/examples/bin/main.

Note: To reset the environment to the default configuration execute:

$ source ./env/morello-sdk-restore

Step by step build explanation

In morello-sdk/morello:

env/morello-sdk: set up $PATH for the Morello toolchain
Sourcing this sets up $PATH such that the Morello supporting LLVM overshadows the system one (since not upstreamed yet).
Required for steps 4 to 6
scripts/build-all.sh: Runs all steps in sequence
Download and compile everything. Accepts either --x86_64 or --aarch64. The default is --aarch64 and is assumed if neither is specified.
The --aarch64 switch downloads and builds everything from an aarch64 host.
Passing --x86_64 assumes an x86_64 host
scripts/download-llvm-musl.sh: Download required tools
This clones a binary release of LLVM to llvm, its sources to llvm-project and the musl sources to musl.
Accepts a variable MODE={aarch64, x86_64} and will checkout aarch64 or x86_64 binaries respectively.
NOTE: this process downloads about 3GB. When building on an emulator (e.g. qemu) this can be done on the host machine and copied over.
scripts/build-musl.sh: Build Musl
This runs ./configure && make in musl’s root directory with libshim enabled.
Downloads a few MB of dependencies. Takes a while.
scripts/build-libraries.sh: Build Compiler-RT
This script builds llvm’s compiler-rt and the crt*.o objects.
tools/Makefile: Compile morello_elf
This utility sets up the ELF headers of the Morello binary. Necessary since the ELF format is not finalized yet.
examples/test-app/Makefile: Compile a hello world program
Compiles a simple hello world for the Morello architecture and passes it to morello_elf.
Output is in examples/bin.
examples/morello-heap-app/Makefile: Compile a capability based heap test program
Compiles a simple capability based heap test for the Morello architecture and passes it to morello_elf.
Output is in examples/bin.
examples/morello-stack-app/Makefile: Compile a capability based stack test program
Compiles a simple capability based stack test for the Morello architecture and passes it to morello_elf.
NOTE : To see the differences in behavior in between aarch64 and Morello, it is possible to recompile the same program for aarch64 and compare the results with what happens on Morello. This should point out that just recompiling the same code on Morello makes it more robust and secure.
Output for Morello is in examples/bin.

NOTE: Please refer to the following links to have a clear understanding of the implemented process:

refer to man gcc and look up each argument
refer to the gcc docs and read through the chapters on Standards and Standard Libraries
refer to this gentoo doc for an explanation of what all the crt files do
refer to musl’s source code for what the other crts do
(crt = C RunTime)

Note on samba