192 lines
6 KiB
XML
192 lines
6 KiB
XML
<chapter xmlns="http://docbook.org/ns/docbook"
|
||
xmlns:xlink="http://www.w3.org/1999/xlink"
|
||
xml:id="chap-introduction">
|
||
|
||
<title>Package Notes</title>
|
||
|
||
<para>This chapter contains information about how to use and maintain
|
||
the Nix expressions for a number of specific packages, such as the
|
||
Linux kernel or X.org.</para>
|
||
|
||
|
||
<!--============================================================-->
|
||
|
||
<section>
|
||
|
||
<title>Linux kernel</title>
|
||
|
||
<para>The Nix expressions to build the Linux kernel are in <link
|
||
xlink:href="https://svn.nixos.org/repos/nix/nixpkgs/trunk/pkgs/os-specific/linux/kernel"><filename>pkgs/os-specific/linux/kernel</filename></link>.</para>
|
||
|
||
<para>The function that builds the kernel has an argument
|
||
<varname>kernelPatches</varname> which should be a list of
|
||
<literal>{name, patch, extraConfig}</literal> attribute sets, where
|
||
<varname>name</varname> is the name of the patch (which is included in
|
||
the kernel’s <varname>meta.description</varname> attribute),
|
||
<varname>patch</varname> is the patch itself (possibly compressed),
|
||
and <varname>extraConfig</varname> (optional) is a string specifying
|
||
extra options to be concatenated to the kernel configuration file
|
||
(<filename>.config</filename>).</para>
|
||
|
||
<para>The kernel derivation exports an attribute
|
||
<varname>features</varname> specifying whether optional functionality
|
||
is or isn’t enabled. This is used in NixOS to implement
|
||
kernel-specific behaviour. For instance, if the kernel has the
|
||
<varname>iwlwifi</varname> feature (i.e. has built-in support for
|
||
Intel wireless chipsets), then NixOS doesn’t have to build the
|
||
external <varname>iwlwifi</varname> package:
|
||
|
||
<programlisting>
|
||
modulesTree = [kernel]
|
||
++ pkgs.lib.optional (!kernel.features ? iwlwifi) kernelPackages.iwlwifi
|
||
++ ...;
|
||
</programlisting>
|
||
|
||
</para>
|
||
|
||
<para>How to add a new (major) version of the Linux kernel to Nixpkgs:
|
||
|
||
<orderedlist>
|
||
|
||
<listitem>
|
||
<para>Copy (<command>svn cp</command>) the old Nix expression
|
||
(e.g. <filename>linux-2.6.21.nix</filename>) to the new one
|
||
(e.g. <filename>linux-2.6.22.nix</filename>) and update it.</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Add the new kernel to <filename>all-packages.nix</filename>
|
||
(e.g., create an attribute
|
||
<varname>kernel_2_6_22</varname>).</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Now we’re going to update the kernel configuration. First
|
||
unpack the kernel. Then for each supported platform
|
||
(<literal>i686</literal>, <literal>x86_64</literal>,
|
||
<literal>uml</literal>) do the following:
|
||
|
||
<orderedlist>
|
||
|
||
<listitem>
|
||
<para>Make an <command>svn copy</command> from the old
|
||
config (e.g. <filename>config-2.6.21-i686-smp</filename>) to
|
||
the new one
|
||
(e.g. <filename>config-2.6.22-i686-smp</filename>).</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Copy the config file for this platform
|
||
(e.g. <filename>config-2.6.22-i686-smp</filename>) to
|
||
<filename>.config</filename> in the kernel source tree.
|
||
</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Run <literal>make oldconfig
|
||
ARCH=<replaceable>{i386,x86_64,um}</replaceable></literal>
|
||
and answer all questions. (For the uml configuration, also
|
||
add <literal>SHELL=bash</literal>.) Make sure to keep the
|
||
configuration consistent between platforms (i.e. don’t
|
||
enable some feature on <literal>i686</literal> and disable
|
||
it on <literal>x86_64</literal>).
|
||
</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>If needed you can also run <literal>make
|
||
menuconfig</literal>:
|
||
|
||
<screen>
|
||
$ nix-env -i ncurses
|
||
$ export NIX_CFLAGS_LINK=-lncurses
|
||
$ make menuconfig ARCH=<replaceable>arch</replaceable></screen>
|
||
|
||
</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Make sure that
|
||
<literal>CONFIG_FB_TILEBLITTING</literal> is <emphasis>not
|
||
set</emphasis> (otherwise <command>fbsplash</command> won't
|
||
work). This option has a tendency to be enabled as a
|
||
side-effect of other options. If it is, investigate why
|
||
(there's probably another option that forces it to be on)
|
||
and fix it.</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Copy <filename>.config</filename> over the new config
|
||
file (e.g. <filename>config-2.6.22-i686-smp</filename>).</para>
|
||
</listitem>
|
||
|
||
</orderedlist>
|
||
|
||
</para>
|
||
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>Test building the kernel: <literal>nix-build -A
|
||
kernel_2_6_22</literal>. If it compiles, ship it! For extra
|
||
credit, try booting NixOS with it.</para>
|
||
</listitem>
|
||
|
||
<listitem>
|
||
<para>It may be that the new kernel requires updating the external
|
||
kernel modules and kernel-dependent packages listed in the
|
||
<varname>kernelPackagesFor</varname> function in
|
||
<filename>all-packages.nix</filename> (such as the NVIDIA drivers,
|
||
AUFS, splashutils, etc.). If the updated packages aren’t
|
||
backwards compatible with older kernels, you need to keep the
|
||
older versions and use some conditionals. For example, new
|
||
kernels require splashutils 1.5 while old kernel require 1.3, so
|
||
<varname>kernelPackagesFor</varname> says:
|
||
|
||
<programlisting>
|
||
splashutils =
|
||
if kernel.features ? fbSplash then splashutils_13 else
|
||
if kernel.features ? fbConDecor then splashutils_15 else
|
||
null;
|
||
|
||
splashutils_13 = ...;
|
||
splashutils_15 = ...;</programlisting>
|
||
|
||
</para>
|
||
</listitem>
|
||
|
||
</orderedlist>
|
||
|
||
</para>
|
||
|
||
</section>
|
||
|
||
|
||
<!--============================================================-->
|
||
|
||
<section>
|
||
<title>X.org</title>
|
||
<para>* Expression is auto-generated</para>
|
||
<para>* How to update</para>
|
||
</section>
|
||
|
||
|
||
<!--============================================================-->
|
||
|
||
<section>
|
||
<title>Gnome</title>
|
||
<para>* Expression is auto-generated</para>
|
||
<para>* How to update</para>
|
||
</section>
|
||
|
||
|
||
<!--============================================================-->
|
||
|
||
<section>
|
||
<title>GCC</title>
|
||
<para>…</para>
|
||
</section>
|
||
|
||
|
||
</chapter>
|