Both building and booting a directory image is much faster than
building or booting a disk image so let's default to a directory
image.
In CI, we stick to a disk image to make sure that keeps working as
well.
The only extra dependency this introduces is virtiofsd which is
packaged in all distributions except Debian stable. For users
hacking on systemd on Debian stable, a disk image can be built by
writing the following to mkosi.local.conf:
```
[Output]
Format=disk
```
Now that mkosi-kernel is a thing, this logic in systemd is just mostly
bitrotting since I just use mkosi-kernel these days. If I ever need to
hack on systemd and the kernel in tandem, I'll just add support for
building systemd to mkosi-kernel instead, so let's drop the support for
building a custom kernel in systemd's mkosi configuration.
- Use mkosi.images/ instead of mkosi.presets/
- Use the .chroot suffix to run scripts in the image
- Use BuildSources= match for the kernel build
- Move 10-systemd.conf to mkosi.conf and rely on mkosi.local.conf
for local configuration
Instead of using ExtraTrees=, let's use the new RuntimeTrees= option
to mount the full repository into the VM/container. Let's also store
the sources under /usr/src/systemd and update the gdbinit file and
vscode HACKING guide section to match the new location.
Let's mention that we just need the latest stable release of mkosi,
not the latest git commit. We also split the instructions for building
on the host and the instructions for building with mkosi into two blocks,
as it's not required to build on the host anymore to build with mkosi.
Since mkosi is now smart enough to drop the caches when the list of
packages changes, let's enable Incremental= mode by default to ensure
a good experience for anyone new to hacking on systemd with mkosi.
The kernel, systemd, and many other things print their version during boot.
sd-boot and sd-stub are also important, so let's print the version if EFI_DEBUG.
(If !EFI_DEBUG, continue to be quiet.)
When updating the docs, I saw that that the text in HACKING.md was out of date.
Instead of trying to update the instructions there, make it shorter and refer
the reader to tools/debug-sd-boot.sh for details.
Let's start moving towards a more involved partitioning setup to
test our stuff more when using mkosi.
The root partition is generated on boot with systemd-repart.
CentOS supports neither erofs nor btrfs so we use squashfs and xfs
instead.
We also enable SecureBoot= locally for additional coverage. This
and the use of verity means users need to run `mkosi genkey` once
to generate the keys necessary to do secure boot and verity.
- Drop Netdev= as it was removed in mkosi
- Always install python-psutil in the final image (required for networkd tests)
- Always Install python-pytest in the final image (required for ukify tests)
- Use the narrow glob for all centos python packages
- Drop the networkd mkosi config files (the default image can be used instead)
- Use ".conf" as the mkosi config file suffix everywhere
- Copy src/ to /root/src in the final image and set gdb substitute path in
.gdbinit to make gdb work properly
(The one case that is left unchanged is '< <(subcommand)'.)
This way, the style with no gap was already dominant. This way, the reader
immediately knows that ' < ' is a comparison operator and ' << ' is a shift.
In a few cases, replace custom EOF replacement by just EOF. There is no point
in using someting like "_EOL" unless "EOF" appears in the text.
If mkosi.kernel/ exists, the mkosi script will try to build a kernel
image from it. We use the architecture defconfig as a base and add
our own extra configuration on top.
We also add some extra tooling to the build image required to build
the kernel and include some documentation in HACKING.md on how to
use this new feature.
To avoid the kernel sources from being copied into the build or
final image (which we don't want because it takes a while), we put
the mkosi.kernel/ directory in .gitignore and use
"SourceFileTransfer=mount" so that the sources are still accessible
in the build image.
- Extra memory because ASAN needs it
- The environment variables to make the sanitizers more useful
- LD_PRELOAD because the ASAN DSO needs to be the first in the list
- The sanitizer library packages
- Disable syscall filters because they interfere with ASAN
- Disable systemd-hwdb-update because it's super slow when systemd-hwdb
is built with sanitizers
- Take the value for meson's b_sanitize option from the SANITIZERS
environment variable
With meson-0.60, meson compile stopped working with some targets:
$ meson compile -C build update-man-rules
ERROR: Can't invoke target `update-man-rules`: ambiguous name. Add target type and/or path: `PATH/NAME:TYPE`
This is obviously a regression in meson, but based on a chat with the
maintainers, it seems that there's some disagreement as to whether 'meson
compile' is useful and how exactly it should work. Since we're already at
meson 0.60.3 and this hasn't been fixed, and people generally don't seem to
consider this an issue, let's return to documenting the usual practice of
'ninja -C build' that just works everywhere.
(Since nobody has raised any fuss in systemd, it means that people are
generally using the shorter form during development too. I only noticed
because I pasted a command from the release docs when preparing -rc1.)
mkosi automatically builds for the host distro which seems a much
better default to encourage since dnf won't be installed on any host
system that's not Fedora anyway.
I have no idea if this is going to cause rendering problems, and it is fairly
hard to check. So let's just merge this, and if it github markdown processor
doesn't like it, revert.
With this change, "mkosi build" will automatically build systemd for the
current distro without any further configuration. If people want to do a
cross-distro build by default, they can still create mkosi.default, but I
assume that this is relatively rare.
If people have symlinked mkosi.default to one of the files in .mkosi/, they'll
need to adjust the symlink.
(Building without configuration would always fail, since systemd has many many
required dependencies. I think it's nicer to do the most commonly expected
thing by default, i.e. rebuild for the current distro.)
Mkosi is nowadays packaged for most distros, so recommend installing of distro
packages as the primary installation mechanism.
While it's perfectly possible today to completely rely on mkosi for
building and testing systemd, to get code completion and other IDE
niceties to work properly, it's still necessary to build systemd
locally.
Recently, mkosi gained the ability to allow external programs to
communicate with the build script. We can use this feature to run
the clangd language server in the mkosi build image via a custom
build script to provide IDE features in editors without requiring
developers to build systemd on the host or install any of systemd's
build dependencies locally.
This commit adds the necessary information on how to set this up
to HACKING.md.
This only changes documentation. In various places we call "ninja"
directly. I figured it would be safer to leave those in place for now,
given the meson replacement commands lines appears to be supported in
newer meson versions only.
