Linux From Scratch 7.7 Systemd

September 15, 2015

Fahmi Ahmad

Downloading the book (HTML version or PDF)

$ wget http://www.linuxfromscratch.org/lfs/downloads/stable-systemd/LFS-BOOK-7.7-systemd.pdf

Host System\ Thinkpad X61, 2GB of RAM, Core2 Duo T8100 2.10GHz\ Hardened-Gentoo x86_64\ GPT Partition\ 172.16.0.66\ Separate partition /dev/sda4, for LFS

Host Partition:\ Device Start End Sectors Size Type\ /dev/sda1 2048 6143 4096 2M BIOS boot\ /dev/sda2 6144 268287 262144 128M Linux filesystem\ /dev/sda3 268288 8656895 8388608 4G Linux filesystem\ /dev/sda4 8656896 29628415 20971520 10G Linux filesystem\ /dev/sda5 29628416 234439599 204811184 97.7G Linux filesystem

Creating $LFS variable

$ ssh fahmi@172.16.0.66
$ su -
root# mkdir /mnt/lfs
root# export LFS=/mnt/lfs
root# vim /etc/profile
export LFS=/mnt/lfs

Creating Tmux session, Downloading needed files and Checking the MD5 hash of the downloaded files

$ ssh fahmi@172.16.0.66
fahmi@gentoo $ tmux new -s LFS
fahmi@gentoo $ su -
root# mount /dev/sda4 /mnt/lfs
root# cd /mnt/lfs
root# mkdir sources
root# wget http://www.linuxfromscratch.org/lfs/downloads/stable-systemd/md5sums
root# wget http://www.linuxfromscratch.org/lfs/downloads/stable-systemd/wget-list
root# wget --input-file=wget-list --continue --directory-prefix=$LFS/sources
root# cp mv md5sums wget-list sources/
root# pushd $LFS/sources
root# md5sums -c md5sums
root# popd

Creating $LFS/tools directory and Creating the /tools symlink on the host system

root# mkdir -v $LFS/tools
root# ln -sv $LFS/tools /
root# groupadd lfs
root# useradd -s /bin/bash -g lfs -m -k /dev/null lfs
root# passwd lfs
root# chown -v lfs $LFS/tools
root# chown -v lfs $LFS/sources
root# su - lfs

Setting Up the environment

lfs@gentoo$ cat > ~/.bash_profile << "EOF"
   > exec env -i HOME=$HOME TERM=$TERM PS1='\u:\w$ ' /bin/bash
   > EOF
   > lfs@gentoo$ cat > \~/.bashrc << "EOF"
   > set +h
   > umask 022
   > LFS=/mnt/lfs
   > LC_ALL=POSIX
   > LFS_TGT=$(uname -m)-lfs-linux-gnu
   > PATH=/tools/bin:/bin:/usr/bin
   > export LFS LC_ALL LFS_TGT PATH
   > EOF
   > lfs@gentoo$ source \~/.bash_profile
   > lfs@gentoo$ export MAKEFLAGS='-j 3'

**Important Notice:**

Constructing a Temporary System
To re-emphasize the build process:
1. Place all the sources and patches in a directory that will be accessible from the chroot environment such as /mnt/lfs/sources/. Do not put sources in /mnt/lfs/tools/.
2. Change to the sources directory.
3. For each package:
   a. Using the tar program, extract the package to be built. In Chapter 5, ensure you are the lfs user when extracting the package.
   b. Change to the directory created when the package was extracted.
   c. Follow the book's instructions for building the package.
   d. Change back to the sources directory.
   e. Delete the extracted source directory and any `<package>-build` directories that were created in the build process unless instructed otherwise.
-> If you mount your partition on /mnt/lfs and set up the environment variable the same as the book told you, copy-paste is your friend.\
-> Always remember, during constructing a temporary system, you're compiling program inside $LFS/sources.

Several Example of compiling programs:

BINUTILS

lfs@gentoo$ echo $LFS
/mnt/lfs
lfs@gentoo$ cd $LFS
lfs@gentoo$ cd sources
lfs@gentoo$ tar xjvf binutils-2.25.tar.bz2
lfs@gentoo$ cd binutils-2.25
lfs@gentoo$ mkdir -v ../binutils-build
lfs@gentoo$ cd ../binutils-build
lfs@gentoo$ ../binutils-2.25/configure     \
> \--prefix=/tools            \
>     --with-sysroot=$LFS        \
>     --with-lib-path=/tools/lib \
>     --target=$LFS_TGT          \
>     --disable-nls              \
>     --disable-werror
> lfs@gentoo$ make
> lfs@gentoo$ case $(uname -m) in
>   x86_64) mkdir -v /tools/lib && ln -sv lib /tools/lib64 ;;
> esac
> lfs@gentoo$ make install

GCC

lfs@gentoo$ cd ../
lfs@gentoo$ tar xjvf gcc-4.9.2.tar.bz2
lfs@gentoo$ rm -rf binutils-build/
lfs@gentoo$ cd gcc-4.9.2
lfs@gentoo$ tar -xf ../mpfr-3.1.2.tar.xz
lfs@gentoo$ mv -v mpfr-3.1.2 mpfr
lfs@gentoo$ tar -xf ../gmp-6.0.0a.tar.xz
lfs@gentoo$ mv -v gmp-6.0.0 gmp
lfs@gentoo$ tar -xf ../mpc-1.0.2.tar.gz
lfs@gentoo$ mv -v mpc-1.0.2 mpc
lfs@gentoo$ for file in \
$(find gcc/config -name linux64.h -o -name linux.h -o -name sysv4.h)
do
  cp -uv $file{,.orig}
  sed -e 's@/lib(64)?(32)?/ld@/tools&@g' \
      -e 's@/usr@/tools@g' $file.orig > $file
  echo '
#undef STANDARD_STARTFILE_PREFIX_1
#undef STANDARD_STARTFILE_PREFIX_2
#define STANDARD_STARTFILE_PREFIX_1 "/tools/lib/"
#define STANDARD_STARTFILE_PREFIX_2 ""' >> $file
touch $file.orig
done
lfs@gentoo$ sed -i '/k prot/agcc_cv_libc_provides_ssp=yes' gcc/configure
lfs@gentoo$ mkdir -v ../gcc-build
lfs@gentoo$ cd ../gcc-build
lfs@gentoo$ ../gcc-4.9.2/configure                             \
    --target=$LFS_TGT                              \
    --prefix=/tools                                \
    --with-sysroot=$LFS                            \
    --with-newlib                                  \
    --without-headers                              \
    --with-local-prefix=/tools                     \
    --with-native-system-header-dir=/tools/include \
    --disable-nls                                  \
    --disable-shared                               \
    --disable-multilib                             \
    --disable-decimal-float                        \
    --disable-threads                              \
    --disable-libatomic                            \
    --disable-libgomp                              \
    --disable-libitm                               \
    --disable-libquadmath                          \
    --disable-libsanitizer                         \
    --disable-libssp                               \
    --disable-libvtv                               \
    --disable-libcilkrts                           \
    --disable-libstdc++-v3                         \
    --enable-languages=c,c++
lfs@gentoo$ make
lfs@gentoo$ make install

LINUX-3.19 API HEADERS

lfs@gentoo$ cd ../
lfs@gentoo$ tar xvf linux-3.19.tar.xz
lfs@gentoo$ rm -rf gcc-build/
lfs@gentoo$ cd linux-3.19
lfs@gentoo$ make mrproper
lfs@gentoo$ make INSTALL_HDR_PATH=dest headers_install
lfs@gentoo$ cp -rv dest/include/* /tools/include

-> I'm not gonna elaborate the whole process, so read the book, guys :).\ -> I suggest you perform the "sanity check" if you're told to do so.

Stripping

6. lfs@gentoo$ strip --strip-debug /tools/lib/*
   lfs@gentoo$ /usr/bin/strip --strip-unneeded /tools/{,s}bin/*

Save more

lfs@gentoo$ rm -rf /tools/{,share}/{info,man,doc}

Changing the Ownership of $LFS/tools
```
root# chown -R root:root $LFS/tools
```

Preparing Virtual Kernel File Systems

root# mkdir -pv $LFS/{dev,proc,sys,run}

Creating Initial Device Nodes

root# mknod -m 600 $LFS/dev/console c 5 1
root# mknod -m 666 $LFS/dev/null c 1 3

Mounting and Populating /dev
```
root# mount -v --bind /dev $LFS/dev
```

Mounting Virtual Kernel File Systems

root# mount -vt devpts devpts $LFS/dev/pts -o gid=5,mode=620
root# mount -vt proc proc $LFS/proc
root# mount -vt sysfs sysfs $LFS/sys
root# mount -vt tmpfs tmpfs $LFS/run

For some host systems, which its /dev/shm is a symbolic link to /run/shm:
```
root# if [ -h $LFS/dev/shm ]; then
   mkdir -pv $LFS/$(readlink $LFS/dev/shm)
   fi
```
-> If you reboot the server, before chrooting into LFS environment, do Mounting and Populating /dev and Mounting Virtual Kernel File Systems

-> If you need package management, Install it now. Especially if you want LFS to be your primary Distro Linux. Just keep in mind, you have to maintain the software yourself, it's too much work.

Entering the Chroot Environment

root# chroot "$LFS" /tools/bin/env -i \
    HOME=/root \
    TERM="$TERM" \
    PS1='\u:\w\$ ' \
    PATH=/bin:/usr/bin:/sbin:/usr/sbin:/tools/bin \
    /tools/bin/bash --login +h

This is how it looks like

root

Creating Directories

root# mkdir -pv /{bin,boot,etc/{opt,sysconfig},home,lib/firmware,mnt,opt}
root# mkdir -pv /{media/{floppy,cdrom},sbin,srv,var}
root# install -dv -m 0750 /root
root# install -dv -m 1777 /tmp /var/tmp
root# mkdir -pv /usr/{,local/}{bin,include,lib,sbin,src}
root# mkdir -pv /usr/{,local/}share/{color,dict,doc,info,locale,man}
root# mkdir -v /usr/{,local/}share/{misc,terminfo,zoneinfo}
root# mkdir -v /usr/libexec
root# mkdir -pv /usr/{,local/}share/man/man{1..8}
root# case $(uname -m) in
> x86_64) ln -sv lib /lib64
> ln -sv lib /usr/lib64
> ln -sv lib /usr/local/lib64 ;;
>esac

root# mkdir -v /var/{log,mail,spool}\
root# ln -sv /run /var/run\
root# ln -sv /run/lock /var/lock\
root# mkdir -pv /var/{opt,cache,lib/{color,misc,locate},local}

Creating Essential Files and Symlinks

root# ln -sv /tools/bin/{bash,cat,echo,pwd,stty} /bin
root# ln -sv /tools/bin/perl /usr/bin
root# ln -sv /tools/lib/libgcc_s.so{,.1} /usr/lib
root# ln -sv /tools/lib/libstdc++.so{,.6} /usr/lib
root# sed 's/tools/usr/' /tools/lib/libstdc++.la > /usr/lib/libstdc++.la
root# ln -sv bash /bin/sh
root# ln -sv /proc/self/mounts /etc/mtab
root# cat > /etc/passwd <root:x:0:0:root:/root:/bin/bash
>bin:x:1:1:bin:/dev/null:/bin/false
>daemon:x:6:6:Daemon User:/dev/null:/bin/false
>messagebus:x:18:18:D-Bus Message Daemon User:/var/run/dbus:/bin/false
>systemd-bus-proxy:x:72:72:systemd Bus Proxy:/:/bin/false
>systemd-journal-gateway:x:73:73:systemd Journal Gateway:/:/bin/false
>systemd-journal-remote:x:74:74:systemd Journal Remote:/:/bin/false
>systemd-journal-upload:x:75:75:systemd Journal Upload:/:/bin/false
>systemd-network:x:76:76:systemd Network Management:/:/bin/false
>systemd-resolve:x:77:77:systemd Resolver:/:/bin/false
>systemd-timesync:x:78:78:systemd Time Synchronization:/:/bin/false
>nobody:x:99:99:Unprivileged User:/dev/null:/bin/false
>EOF
root# cat > /etc/group <root:x:0:
>bin:x:1:daemon
>sys:x:2:
>kmem:x:3:
>tape:x:4:
>tty:x:5:
>daemon:x:6:
>floppy:x:7:
>disk:x:8:
>lp:x:9:
>dialout:x:10:
>audio:x:11:
>video:x:12:
>utmp:x:13:
>usb:x:14:
>cdrom:x:15:
>adm:x:16:
>messagebus:x:18:
>systemd-journal:x:23:
>input:x:24:
>mail:x:34:
>systemd-bus-proxy:x:72:
>systemd-journal-gateway:x:73:
>systemd-journal-remote:x:74:
>systemd-journal-upload:x:75:
>systemd-network:x:76:
>systemd-resolve:x:77:
>systemd-timesync:x:78:
>nogroup:x:99:
>users:x:999:
>EOF
root# exec /tools/bin/bash --login +h
root# touch /var/log/{btmp,lastlog,wtmp}
root# chgrp -v utmp /var/log/lastlog
root# chmod -v 664 /var/log/lastlog
root# chmod -v 600 /var/log/btmp

A few suggestion during Installing Basic System Software:\ -> Perform every test suite. Most of them are mandatory\ -> Glibc, GCC, linux kernel will take very long time to compile. Be patient :)\ -> Perform every "sanity check" if you're told to.\ -> Don't forget, "cd /sources"

Stripping Again\ root# logout\ Reenter Chroot Environment with:

root# chroot $LFS /tools/bin/env -i \
HOME=/root TERM=$TERM PS1='\u:\w\$ ' \
PATH=/bin:/usr/bin:/sbin:/usr/sbin \
/tools/bin/bash --login
root# /tools/bin/find /{,usr/}{bin,lib,sbin} -type f \
-exec /tools/bin/strip --strip-debug '{}' ';'
root# rm -rf /tmp/*

Modified Chroot Command, do it every time you're entering the chroot environment.

root# chroot "$LFS" /usr/bin/env -i \
HOME=/root TERM="$TERM" PS1='\u:\w\$ ' \
PATH=/bin:/usr/bin:/sbin:/usr/sbin \
/bin/bash --login

-> You can remove /tools now, but you will also remove the temporary copies of Tcl, Expect, and DejaGNU which were used for running the toolchain tests.\ -> I will skip the Basic System Configuration

Making the LFS Bootable