.. _changes:

  Minimal requerements to compile the Kernel
  ++++++++++++++++++++++++++++++++++++++++++

  Intro
  =====
  
  This document is designed to provide a list of the minimum levels of

  software necessary to run the 4.x kernels.

  
  This document is originally based on my "Changes" file for 2.0.x kernels
  and therefore owes credit to the same people as that file (Jared Mauch,
  Axel Boldt, Alessandro Sigala, and countless other users all over the
  'net).

  Current Minimal Requirements

  ****************************

  Upgrade to at **least** these software revisions before thinking you've

  encountered a bug!  If you're unsure what version you're currently
  running, the suggested command should tell you.

  Again, keep in mind that this list assumes you are already functionally
  running a Linux kernel.  Also, not all tools are necessary on all
  systems; obviously, if you don't have any ISDN hardware, for example,
  you probably needn't concern yourself with isdn4k-utils.

  ====================== ===============  ========================================
          Program        Minimal version       Command to check the version
  ====================== ===============  ========================================
  GNU C                  3.2              gcc --version
  GNU make               3.80             make --version
  binutils               2.12             ld -v
  util-linux             2.10o            fdformat --version
  module-init-tools      0.9.10           depmod -V
  e2fsprogs              1.41.4           e2fsck -V
  jfsutils               1.1.3            fsck.jfs -V
  reiserfsprogs          3.6.3            reiserfsck -V
  xfsprogs               2.6.0            xfs_db -V
  squashfs-tools         4.0              mksquashfs -version
  btrfs-progs            0.18             btrfsck
  pcmciautils            004              pccardctl -V
  quota-tools            3.09             quota -V
  PPP                    2.4.0            pppd --version
  isdn4k-utils           3.1pre1          isdnctrl 2>&1|grep version
  nfs-utils              1.0.5            showmount --version
  procps                 3.2.0            ps --version
  oprofile               0.9              oprofiled --version
  udev                   081              udevd --version
  grub                   0.93             grub --version || grub-install --version
  mcelog                 0.6              mcelog --version
  iptables               1.4.2            iptables -V
  openssl & libcrypto    1.0.0            openssl version
  bc                     1.06.95          bc --version

  Sphinx\ [#f1]_	       1.2		sphinx-build --version

  ====================== ===============  ========================================

  .. [#f1] Sphinx is needed only to build the Kernel documentation

  
  Kernel compilation

  ******************

  
  GCC
  ---
  
  The gcc version requirements may vary depending on the type of CPU in your

  computer.

  
  Make
  ----

  You will need GNU make 3.80 or later to build the kernel.

  
  Binutils
  --------

  Linux on IA-32 has recently switched from using ``as86`` to using ``gas`` for
  assembling the 16-bit boot code, removing the need for ``as86`` to compile

  your kernel.  This change does, however, mean that you need a recent
  release of binutils.

  Perl
  ----

  You will need perl 5 and the following modules: ``Getopt::Long``,
  ``Getopt::Std``, ``File::Basename``, and ``File::Find`` to build the kernel.

  BC
  --
  
  You will need bc to build kernels 3.10 and higher

  OpenSSL
  -------
  
  Module signing and external certificate handling use the OpenSSL program and
  crypto library to do key creation and signature generation.
  
  You will need openssl to build kernels 3.7 and higher if module signing is
  enabled.  You will also need openssl development packages to build kernels 4.3
  and higher.

  System utilities

  ****************

  
  Architectural changes
  ---------------------
  
  DevFS has been obsoleted in favour of udev
  (http://www.kernel.org/pub/linux/utils/kernel/hotplug/)
  
  32-bit UID support is now in place.  Have fun!
  
  Linux documentation for functions is transitioning to inline
  documentation via specially-formatted comments near their
  definitions in the source.  These comments can be combined with the
  SGML templates in the Documentation/DocBook directory to make DocBook
  files, which can then be converted by DocBook stylesheets to PostScript,
  HTML, PDF files, and several other formats.  In order to convert from
  DocBook format to a format of your choice, you'll need to install Jade as
  well as the desired DocBook stylesheets.
  
  Util-linux
  ----------

  New versions of util-linux provide ``fdisk`` support for larger disks,

  support new options to mount, recognize more supported partition
  types, have a fdformat which works with 2.4 kernels, and similar goodies.
  You'll probably want to upgrade.
  
  Ksymoops
  --------

  If the unthinkable happens and your kernel oopses, you may need the
  ksymoops tool to decode it, but in most cases you don't.

  It is generally preferred to build the kernel with ``CONFIG_KALLSYMS`` so

  that it produces readable dumps that can be used as-is (this also
  produces better output than ksymoops).  If for some reason your kernel

  is not build with ``CONFIG_KALLSYMS`` and you have no way to rebuild and

  reproduce the Oops with that option, then you can still decode that Oops
  with ksymoops.

  
  Module-Init-Tools
  -----------------

  A new module loader is now in the kernel that requires ``module-init-tools``

  to use.  It is backward compatible with the 2.4.x series kernels.
  
  Mkinitrd
  --------

  These changes to the ``/lib/modules`` file tree layout also require that

  mkinitrd be upgraded.
  
  E2fsprogs
  ---------

  The latest version of ``e2fsprogs`` fixes several bugs in fsck and

  debugfs.  Obviously, it's a good idea to upgrade.
  
  JFSutils
  --------

  The ``jfsutils`` package contains the utilities for the file system.

  The following utilities are available:

  
  - ``fsck.jfs`` - initiate replay of the transaction log, and check

    and repair a JFS formatted partition.

  
  - ``mkfs.jfs`` - create a JFS formatted partition.
  
  - other file system utilities are also available in this package.

  
  Reiserfsprogs
  -------------
  
  The reiserfsprogs package should be used for reiserfs-3.6.x
  (Linux kernels 2.4.x). It is a combined package and contains working

  versions of ``mkreiserfs``, ``resize_reiserfs``, ``debugreiserfs`` and
  ``reiserfsck``. These utils work on both i386 and alpha platforms.

  
  Xfsprogs
  --------

  The latest version of ``xfsprogs`` contains ``mkfs.xfs``, ``xfs_db``, and the
  ``xfs_repair`` utilities, among others, for the XFS filesystem.  It is

  architecture independent and any version from 2.0.0 onward should
  work correctly with this version of the XFS kernel code (2.6.0 or
  later is recommended, due to some significant improvements).

  PCMCIAutils
  -----------

  PCMCIAutils replaces ``pcmcia-cs``. It properly sets up

  PCMCIA sockets at system startup and loads the appropriate modules
  for 16-bit PCMCIA devices if the kernel is modularized and the hotplug
  subsystem is used.

  Quota-tools
  -----------
  
  Support for 32 bit uid's and gid's is required if you want to use
  the newer version 2 quota format.  Quota-tools version 3.07 and
  newer has this support.  Use the recommended version or newer
  from the table above.
  
  Intel IA32 microcode
  --------------------
  
  A driver has been added to allow updating of Intel IA32 microcode,

  accessible as a normal (misc) character device.  If you are not using

  udev you may need to::

  
    mkdir /dev/cpu
    mknod /dev/cpu/microcode c 10 184
    chmod 0644 /dev/cpu/microcode

  
  as root before you can use this.  You'll probably also want to
  get the user-space microcode_ctl utility to use with this.

  udev
  ----

  
  ``udev`` is a userspace application for populating ``/dev`` dynamically with
  only entries for devices actually present. ``udev`` replaces the basic

  functionality of devfs, while allowing persistent device naming for

  devices.

  FUSE
  ----
  
  Needs libfuse 2.4.0 or later.  Absolute minimum is 2.3.0 but mount

  options ``direct_io`` and ``kernel_cache`` won't work.

  Networking

  **********

  
  General changes
  ---------------
  
  If you have advanced network configuration needs, you should probably
  consider using the network tools from ip-route2.
  
  Packet Filter / NAT
  -------------------
  The packet filtering and NAT code uses the same tools like the previous 2.4.x
  kernel series (iptables).  It still includes backwards-compatibility modules
  for 2.2.x-style ipchains and 2.0.x-style ipfwadm.
  
  PPP
  ---
  
  The PPP driver has been restructured to support multilink and to
  enable it to operate over diverse media layers.  If you use PPP,
  upgrade pppd to at least 2.4.0.

  If you are not using udev, you must have the device file /dev/ppp

  which can be made by::

  
    mknod /dev/ppp c 108 0

  
  as root.

  Isdn4k-utils
  ------------
  
  Due to changes in the length of the phone number field, isdn4k-utils
  needs to be recompiled or (preferably) upgraded.
  
  NFS-utils
  ---------

  In ancient (2.4 and earlier) kernels, the nfs server needed to know
  about any client that expected to be able to access files via NFS.  This

  information would be given to the kernel by ``mountd`` when the client
  mounted the filesystem, or by ``exportfs`` at system startup.  exportfs
  would take information about active clients from ``/var/lib/nfs/rmtab``.

  
  This approach is quite fragile as it depends on rmtab being correct
  which is not always easy, particularly when trying to implement

  fail-over.  Even when the system is working well, ``rmtab`` suffers from

  getting lots of old entries that never get removed.

  With modern kernels we have the option of having the kernel tell mountd
  when it gets a request from an unknown host, and mountd can give
  appropriate export information to the kernel.  This removes the

  dependency on ``rmtab`` and means that the kernel only needs to know about

  currently active clients.

  To enable this new functionality, you need to::

    mount -t nfsd nfsd /proc/fs/nfsd

  
  before running exportfs or mountd.  It is recommended that all NFS
  services be protected from the internet-at-large by a firewall where
  that is possible.

  mcelog
  ------

  On x86 kernels the mcelog utility is needed to process and log machine check

  events when ``CONFIG_X86_MCE`` is enabled. Machine check events are errors
  reported by the CPU. Processing them is strongly encouraged.

  Kernel documentation
  ********************
  
  Sphinx
  ------
  
  The ReST markups currently used by the Documentation/ files are meant to be
  built with ``Sphinx`` version 1.2 or upper. If you're desiring to build
  PDF outputs, it is recommended to use version 1.4.6.
  
  .. note::
  
    Please notice that, for PDF and LaTeX output, you'll also need ``XeLaTeX``
    version 3.14159265. Depending on the distribution, you may also need
    to install a series of ``texlive`` packages that provide the minimal
    set of functionalities required for ``XeLaTex`` to work.
  
  Other tools
  -----------
  
  In order to produce documentation from DocBook, you'll also need ``xmlto``.
  Please notice, however, that we're currently migrating all documents to use
  ``Sphinx``.

  Getting updated software
  ========================
  
  Kernel compilation
  ******************

  gcc
  ---

  
  - <ftp://ftp.gnu.org/gnu/gcc/>

  
  Make
  ----

  
  - <ftp://ftp.gnu.org/gnu/make/>

  
  Binutils
  --------

  
  - <ftp://ftp.kernel.org/pub/linux/devel/binutils/>

  OpenSSL
  -------

  
  - <https://www.openssl.org/>

  System utilities
  ****************
  
  Util-linux
  ----------

  
  - <ftp://ftp.kernel.org/pub/linux/utils/util-linux/>

  
  Ksymoops
  --------

  
  - <ftp://ftp.kernel.org/pub/linux/utils/kernel/ksymoops/v2.4/>

  
  Module-Init-Tools
  -----------------

  
  - <ftp://ftp.kernel.org/pub/linux/kernel/people/rusty/modules/>

  
  Mkinitrd
  --------

  
  - <https://code.launchpad.net/initrd-tools/main>

  
  E2fsprogs
  ---------

  
  - <http://prdownloads.sourceforge.net/e2fsprogs/e2fsprogs-1.29.tar.gz>

  
  JFSutils
  --------

  
  - <http://jfs.sourceforge.net/>

  
  Reiserfsprogs
  -------------

  
  - <http://www.kernel.org/pub/linux/utils/fs/reiserfs/>

  
  Xfsprogs
  --------

  
  - <ftp://oss.sgi.com/projects/xfs/>

  Pcmciautils
  -----------

  
  - <ftp://ftp.kernel.org/pub/linux/utils/kernel/pcmcia/>

  Quota-tools

  -----------
  
  - <http://sourceforge.net/projects/linuxquota/>

  DocBook Stylesheets
  -------------------

  
  - <http://sourceforge.net/projects/docbook/files/docbook-dsssl/>

  XMLTO XSLT Frontend
  -------------------

  
  - <http://cyberelk.net/tim/xmlto/>

  Intel P6 microcode
  ------------------

  
  - <https://downloadcenter.intel.com/>

  udev
  ----

  
  - <http://www.freedesktop.org/software/systemd/man/udev.html>

  FUSE
  ----

  
  - <http://sourceforge.net/projects/fuse>

  mcelog
  ------

  
  - <http://www.mcelog.org/>

  Networking
  **********
  
  PPP
  ---

  
  - <ftp://ftp.samba.org/pub/ppp/>

  
  Isdn4k-utils
  ------------

  
  - <ftp://ftp.isdn4linux.de/pub/isdn4linux/utils/>

  
  NFS-utils
  ---------

  
  - <http://sourceforge.net/project/showfiles.php?group_id=14>

  
  Iptables
  --------

  
  - <http://www.iptables.org/downloads.html>

  
  Ip-route2
  ---------

  
  - <https://www.kernel.org/pub/linux/utils/net/iproute2/>

  
  OProfile
  --------

  
  - <http://oprofile.sf.net/download/>

  
  NFS-Utils
  ---------

  
  - <http://nfs.sourceforge.net/>

  
  Kernel documentation
  ********************
  
  Sphinx
  ------
  
  - <http://www.sphinx-doc.org/>