Making a Custom Kernel

• Why compile?
  • Customization
  • Remove bloat
• Getting the kernel source
  • Full source tarball
  • Patches
  • Installing the source
    • For the full tarball:
      • # cd /usr/src
      • # rm linux
      • # tar -zxvf linux-2.2.12.tar.gz
      • # mv linux linux-2.2.12 ; ln -s linux linux-2.2.12
    • For a patch:
      • You need every incremental patch between your current kernel and your target kernel
      • For a compressed patch:
        • # cd /usr/src
        • # zcat patch.gz | patch -p1
      • For an uncompressed patch:
        • # cd /usr/src
        • # patch -p1 < patch.diff
• Configuring the kernel
  • Three different ways to configure the kernel:
    • make config -- text-based Q&A-style configuration
    • make menuconfig -- ncurses-based configuration
    • make xconfig -- X-based configuration
• Building the kernel
  • # make clean
  • # make dep
  • # make [zImage|bzImage|zlilo|bzlilo|zdisk|bzdisk]
• Modules
  • # make modules modules_install
  • using modules
  • why modules?
• Installing the new kernel with LILO
  • Copy the new kernel to /boot: # cp /usr/src/linux/arch/i386/boot/vmlinux /boot/vmlinuz-2.2.12
  • Edit /etc/lilo.conf:
    • Edit the stanza for the old kerel, to change the label name from linux to something else. I prefer to label the current kernel as "linux", and label previous kernels with their version number, ie "linux-2.2.5"
    • Add a new stanza for the new kernel:
      image = /boot/vmlinux-2.2.12
label = linux
  • Run /sbin/lilo -v to reinstall lilo with the new settings
  • Reboot the machine (# shutdown -r now) to use the new kernel