8.75.1. Installation of Udev
Udev is part of the systemd-255 package. Use the systemd-255.tar.xz
file as the source tarball.
Remove two unneeded groups, render
and sgx, from the default udev
rules:
sed -i -e 's/GROUP="render"/GROUP="video"/' \
-e 's/GROUP="sgx", //' rules.d/50-udev-default.rules.in
Remove one udev rule requiring a full Systemd installation:
sed '/systemd-sysctl/s/^/#/' -i rules.d/99-systemd.rules.in
Adjust the hardcoded paths to network configuration files for the
standalone udev installation:
sed '/NETWORK_DIRS/s/systemd/udev/' -i src/basic/path-lookup.h
Prepare Udev for compilation:
mkdir -p build
cd build
meson setup \
--prefix=/usr \
--buildtype=release \
-Dmode=release \
-Ddev-kvm-mode=0660 \
-Dlink-udev-shared=false \
-Dlogind=false \
-Dvconsole=false \
..
The meaning of the meson options:
-
--buildtype=release
-
This switch overrides the default buildtype (“debug”), which
produces unoptimized binaries.
-
-Dmode=release
-
Disable some features considered experimental by upstream.
-
-Ddev-kvm-mode=0660
-
The default udev rule would allow all users to access
/dev/kvm. The editors consider
it dangerous. This option overrides it.
-
-Dlink-udev-shared=false
-
This option prevents udev from linking to the internal
systemd shared library, libsystemd-shared. This library is
designed to be shared by many Systemd components and it's too
overkill for a udev-only installation.
-
-Dlogind=false
-Dvconsole=false
-
These options prevent the generation of several udev rule
files belonging to the other Systemd components that we won't
install.
Get the list of the shipped udev helpers and save it into an
environment variable (exporting it is not strictly necessary, but
it makes building as a regular user or using a package manager
easier):
export udev_helpers=$(grep "'name' :" ../src/udev/meson.build | \
awk '{print $3}' | tr -d ",'" | grep -v 'udevadm')
Only build the components needed for udev:
ninja udevadm systemd-hwdb \
$(ninja -n | grep -Eo '(src/(lib)?udev|rules.d|hwdb.d)/[^ ]*') \
$(realpath libudev.so --relative-to .) \
$udev_helpers
Install the package:
install -vm755 -d {/usr/lib,/etc}/udev/{hwdb.d,rules.d,network}
install -vm755 -d /usr/{lib,share}/pkgconfig
install -vm755 udevadm /usr/bin/
install -vm755 systemd-hwdb /usr/bin/udev-hwdb
ln -svfn ../bin/udevadm /usr/sbin/udevd
cp -av libudev.so{,*[0-9]} /usr/lib/
install -vm644 ../src/libudev/libudev.h /usr/include/
install -vm644 src/libudev/*.pc /usr/lib/pkgconfig/
install -vm644 src/udev/*.pc /usr/share/pkgconfig/
install -vm644 ../src/udev/udev.conf /etc/udev/
install -vm644 rules.d/* ../rules.d/README /usr/lib/udev/rules.d/
install -vm644 $(find ../rules.d/*.rules \
-not -name '*power-switch*') /usr/lib/udev/rules.d/
install -vm644 hwdb.d/* ../hwdb.d/{*.hwdb,README} /usr/lib/udev/hwdb.d/
install -vm755 $udev_helpers /usr/lib/udev
install -vm644 ../network/99-default.link /usr/lib/udev/network
Install some custom rules and support files useful in an LFS
environment:
tar -xvf ../../udev-lfs-20230818.tar.xz
make -f udev-lfs-20230818/Makefile.lfs install
Install the man pages:
tar -xf ../../systemd-man-pages-255.tar.xz \
--no-same-owner --strip-components=1 \
-C /usr/share/man --wildcards '*/udev*' '*/libudev*' \
'*/systemd.link.5' \
'*/systemd-'{hwdb,udevd.service}.8
sed 's|systemd/network|udev/network|' \
/usr/share/man/man5/systemd.link.5 \
> /usr/share/man/man5/udev.link.5
sed 's/systemd\(\\\?-\)/udev\1/' /usr/share/man/man8/systemd-hwdb.8 \
> /usr/share/man/man8/udev-hwdb.8
sed 's|lib.*udevd|sbin/udevd|' \
/usr/share/man/man8/systemd-udevd.service.8 \
> /usr/share/man/man8/udevd.8
rm /usr/share/man/man*/systemd*
Finally, unset the udev_helpers
variable:
unset udev_helpers