1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
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4 | <!ENTITY % general-entities SYSTEM "../general.ent">
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5 | %general-entities;
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6 | ]>
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7 |
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8 | <sect1 id="ch-bootable-kernel" role="wrap">
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9 | <?dbhtml filename="kernel.html"?>
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10 |
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11 | <sect1info condition="script">
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12 | <productname>kernel</productname>
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13 | <productnumber>&linux-version;</productnumber>
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14 | <address>&linux-url;</address>
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15 | </sect1info>
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16 |
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17 | <title>Linux-&linux-version;</title>
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18 |
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19 | <indexterm zone="ch-bootable-kernel">
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20 | <primary sortas="a-Linux">Linux</primary>
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21 | </indexterm>
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22 |
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23 | <sect2 role="package">
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24 | <title/>
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25 |
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26 | <para>The Linux package contains the Linux kernel.</para>
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27 |
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28 | <segmentedlist>
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29 | <segtitle>&buildtime;</segtitle>
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30 | <segtitle>&diskspace;</segtitle>
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31 |
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32 | <seglistitem>
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33 | <seg>&linux-knl-sbu;</seg>
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34 | <seg>&linux-knl-du;</seg>
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35 | </seglistitem>
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36 | </segmentedlist>
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37 |
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38 | </sect2>
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39 |
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40 | <sect2 role="installation">
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41 | <title>Installation of the kernel</title>
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42 |
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43 | <para>Building the kernel involves a few steps—configuration,
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44 | compilation, and installation. Read the <filename>README</filename> file
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45 | in the kernel source tree for alternative methods to the way this book
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46 | configures the kernel.</para>
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47 |
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48 | <important>
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49 | <para>
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50 | Building the linux kernel for the first time is one of the most
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51 | challenging tasks in LFS. Getting it right depends on the specific
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52 | hardware for the target system and your specific needs. There are
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53 | almost 12,000 configuration items that are available for the kernel
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54 | although only about a third of them are needed for most computers. The
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55 | LFS editors recommend that users not familiar with this process follow
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56 | the procedures below fairly closely. The objective is to get an
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57 | initial system to a point where you can log in at the command line when
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58 | you reboot later in <xref linkend="ch-finish-reboot"/>. At his point
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59 | optimization and customization is not a goal.
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60 | </para>
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61 |
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62 |
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63 | <para>
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64 | For general information on kernel configuration see <ulink
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65 | url="&hints-root;kernel-configuration.txt"/>. Additional information
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66 | about configuring and building the kernel can be found at <ulink
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67 | url="&anduin-sources;/kernel-nutshell/"/>.
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68 | These references are a bit
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69 | dated, but still give a reasonable overview of the process.
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70 | </para>
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71 |
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72 | <para>
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73 | If all else fails, you can ask for help on the <ulink
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74 | url="https://www.linuxfromscratch.org/mail.html">lfs-support</ulink>
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75 | mailing list. Note that subscribing is required in order for the list
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76 | to avoid spam.
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77 | </para>
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78 | </important>
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79 |
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80 | <para>Prepare for compilation by running the following command:</para>
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81 |
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82 | <screen><userinput remap="pre">make mrproper</userinput></screen>
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83 |
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84 | <para>This ensures that the kernel tree is absolutely clean. The
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85 | kernel team recommends that this command be issued prior to each
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86 | kernel compilation. Do not rely on the source tree being clean after
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87 | un-tarring.</para>
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88 |
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89 | <para>There are several ways to configure the kernel options. Usually,
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90 | This is done through a menu-driven interface, for example:</para>
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91 |
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92 | <screen role="nodump"><userinput>make menuconfig</userinput></screen>
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93 |
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94 | <variablelist>
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95 | <title>The meaning of optional make environment variables:</title>
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96 |
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97 | <varlistentry>
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98 | <term><parameter>LANG=<host_LANG_value> LC_ALL=</parameter></term>
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99 | <listitem>
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100 | <para>This establishes the locale setting to the one used on the
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101 | host. This may be needed for a proper menuconfig ncurses interface
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102 | line drawing on a UTF-8 linux text console.</para>
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103 |
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104 | <para>If used, be sure to replace
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105 | <replaceable><host_LANG_value></replaceable> by the value of
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106 | the <envar>$LANG</envar> variable from your host. You can
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107 | alternatively use instead the host's value of <envar>$LC_ALL</envar>
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108 | or <envar>$LC_CTYPE</envar>.</para>
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109 | </listitem>
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110 | </varlistentry>
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111 |
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112 | <varlistentry>
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113 | <term><command>make menuconfig</command></term>
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114 | <listitem>
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115 | <para>This launches an ncurses menu-driven interface. For other
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116 | (graphical) interfaces, type <command>make help</command>.</para>
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117 | </listitem>
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118 | </varlistentry>
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119 | </variablelist>
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120 |
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121 | <!-- Support for compiling a keymap into the kernel is deliberately removed -->
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122 |
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123 |
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124 | <note>
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125 | <para>A good starting place for setting up the kernel configuration is to
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126 | run <command>make defconfig</command>. This will set the base
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127 | configuration to a good state that takes your current system architecture
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128 | into account.</para>
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129 |
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130 | <para>Be sure to enable/disable/set the following features or the system might
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131 | not work correctly or boot at all:</para>
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132 |
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133 | <screen role="nodump" revision="sysv">Processor type and features --->
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134 | [*] Build a relocatable kernel [CONFIG_RELOCATABLE]
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135 | [*] Randomize the address of the kernel image (KASLR) [CONFIG_RANDOMIZE_BASE]
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136 | General setup --->
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137 | [ ] Compile the kernel with warnings as errors [CONFIG_WERROR]
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138 | < > Enable kernel headers through /sys/kernel/kheaders.tar.xz [CONFIG_IKHEADERS]
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139 | [ ] Configure standard kernel features (expert users) [CONFIG_EXPERT]
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140 | General architecture-dependent options --->
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141 | [*] Stack Protector buffer overflow detection [CONFIG_STACKPROTECTOR]
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142 | [*] Strong Stack Protector [CONFIG_STACKPROTECTOR_STRONG]
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143 | Device Drivers --->
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144 | Graphics support --->
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145 | Frame buffer Devices --->
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146 | <*> Support for frame buffer devices --->
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147 | Console display driver support --->
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148 | [*] Framebuffer Console support [CONFIG_FRAMEBUFFER_CONSOLE]
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149 | Generic Driver Options --->
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150 | [ ] Support for uevent helper [CONFIG_UEVENT_HELPER]
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151 | [*] Maintain a devtmpfs filesystem to mount at /dev [CONFIG_DEVTMPFS]
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152 | [*] Automount devtmpfs at /dev, after the kernel mounted the rootfs [CONFIG_DEVTMPFS_MOUNT]</screen>
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153 |
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154 | <screen role="nodump" revision="systemd">Processor type and features --->
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155 | [*] Build a relocatable kernel [CONFIG_RELOCATABLE]
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156 | [*] Randomize the address of the kernel image (KASLR) [CONFIG_RANDOMIZE_BASE]
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157 | General setup --->
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158 | [ ] Compile the kernel with warnings as errors [CONFIG_WERROR]
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159 | [ ] Auditing Support [CONFIG_AUDIT]
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160 | CPU/Task time and stats accounting --->
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161 | [*] Pressure stall information tracking [CONFIG_PSI]
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162 | [ ] Require boot parameter to enable pressure stall information tracking [CONFIG_PSI_DEFAULT_DISABLED]
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163 | < > Enable kernel headers through /sys/kernel/kheaders.tar.xz [CONFIG_IKHEADERS]
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164 | [*] Control Group support [CONFIG_CGROUPS] --->
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165 | [*] Memory controller [CONFIG_MEMCG]
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166 | [ ] Enable deprecated sysfs features to support old userspace tools [CONFIG_SYSFS_DEPRECATED]
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167 | [ ] Configure standard kernel features (expert users) [CONFIG_EXPERT]
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168 | General architecture-dependent options --->
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169 | [*] Enable seccomp to safely compute untrusted bytecode [CONFIG_SECCOMP]
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170 | [*] Stack Protector buffer overflow detection [CONFIG_STACKPROTECTOR]
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171 | [*] Strong Stack Protector [CONFIG_STACKPROTECTOR_STRONG]
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172 | [*] Networking support ---> [CONFIG_NET]
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173 | Networking options --->
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174 | [*] TCP/IP networking [CONFIG_INET]
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175 | <*> The IPv6 protocol [CONFIG_IPV6]
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176 | Device Drivers --->
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177 | Generic Driver Options --->
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178 | [ ] Support for uevent helper [CONFIG_UEVENT_HELPER]
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179 | [*] Maintain a devtmpfs filesystem to mount at /dev [CONFIG_DEVTMPFS]
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180 | [*] Automount devtmpfs at /dev, after the kernel mounted the rootfs [CONFIG_DEVTMPFS_MOUNT]
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181 | Firmware Loader --->
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182 | [ ] Enable the firmware sysfs fallback mechanism [CONFIG_FW_LOADER_USER_HELPER]
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183 | Firmware Drivers --->
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184 | [*] Export DMI identification via sysfs to userspace [CONFIG_DMIID]
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185 | Graphics support --->
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186 | Frame buffer Devices --->
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187 | <*> Support for frame buffer devices --->
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188 | Console display driver support --->
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189 | [*] Framebuffer Console support [CONFIG_FRAMEBUFFER_CONSOLE]
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190 | File systems --->
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191 | [*] Inotify support for userspace [CONFIG_INOTIFY_USER]
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192 | Pseudo filesystems --->
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193 | [*] Tmpfs POSIX Access Control Lists [CONFIG_TMPFS_POSIX_ACL]</screen>
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194 |
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195 | <para>Enable some additional features if you are building a 64-bit
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196 | system. If you are using menuconfig, enable them in the order of
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197 | <parameter>CONFIG_PCI_MSI</parameter> first, then
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198 | <parameter>CONFIG_IRQ_REMAP</parameter>, at last
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199 | <parameter>CONFIG_X86_X2APIC</parameter> because an option only
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200 | shows up after its dependencies are selected.</para>
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201 |
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202 | <screen role="nodump">Processor type and features --->
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203 | [*] Support x2apic [CONFIG_X86_X2APIC]
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204 | Device Drivers --->
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205 | [*] PCI Support ---> [CONFIG_PCI]
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206 | [*] Message Signaled Interrupts (MSI and MSI-X) [CONFIG_PCI_MSI]
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207 | [*] IOMMU Hardware Support ---> [CONFIG_IOMMU_SUPPORT]
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208 | [*] Support for Interrupt Remapping [CONFIG_IRQ_REMAP]</screen>
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209 |
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210 | <para>If you are building a 32-bit system running on a hardware
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211 | with RAM more than 4GB, adjust the configuration so the kernel will
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212 | be able to use up to 64GB physical RAM:</para>
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213 |
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214 | <screen role="nodump">Processor type and features --->
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215 | High Memory Support --->
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216 | (X) 64GB [CONFIG_HIGHMEM64G]</screen>
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217 |
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218 | <para>If the partition for the LFS system is in a NVME SSD (i. e. the
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219 | device node for the partition is <filename>/dev/nvme*</filename>
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220 | instead of <filename>/dev/sd*</filename>), enable NVME support or
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221 | the LFS system won't boot:</para>
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222 |
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223 | <screen role="nodump">Device Drivers --->
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224 | NVME Support --->
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225 | <*> NVM Express block device [CONFIG_BLK_DEV_NVME]</screen>
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226 | </note>
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227 |
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228 | <note revision="systemd">
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229 | <para>While "The IPv6 Protocol" is not strictly
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230 | required, it is highly recommended by the systemd developers.</para>
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231 | </note>
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232 |
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233 | <para>There are several other options that may be desired
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234 | depending on the requirements for the system. For a list of options needed
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235 | for BLFS packages, see the <ulink
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236 | url="&lfs-root;blfs/view/&short-version;/longindex.html#kernel-config-index">BLFS
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237 | Index of Kernel Settings</ulink>.</para>
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238 |
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239 | <note>
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240 | <para>If your host hardware is using UEFI and you wish to boot the
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241 | LFS system with it, you should adjust some kernel configuration
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242 | following <ulink url="&blfs-book;postlfs/grub-setup.html#uefi-kernel">
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243 | the BLFS page</ulink> <emphasis role='bold'>even if you'll use the
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244 | UEFI bootloader from the host distro</emphasis>.</para>
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245 | </note>
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246 |
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247 | <variablelist>
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248 | <title>The rationale for the above configuration items:</title>
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249 |
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250 | <varlistentry>
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251 | <term><parameter>Randomize the address of the kernel image (KASLR)</parameter></term>
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252 | <listitem>
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253 | <para>Enable ASLR for kernel image, to mitigate some attacks based
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254 | on fixed addresses of sensitive data or code in the kernel.</para>
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255 | </listitem>
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256 | </varlistentry>
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257 |
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258 | <varlistentry>
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259 | <term>
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260 | <parameter>
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261 | Compile the kernel with warnings as errors
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262 | </parameter>
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263 | </term>
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264 | <listitem>
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265 | <para>This may cause building failure if the compiler and/or
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266 | configuration are different from those of the kernel
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267 | developers.</para>
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268 | </listitem>
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269 | </varlistentry>
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270 |
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271 | <varlistentry>
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272 | <term>
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273 | <parameter>
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274 | Enable kernel headers through /sys/kernel/kheaders.tar.xz
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275 | </parameter>
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276 | </term>
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277 | <listitem>
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278 | <para>This will require <command>cpio</command> building the kernel.
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279 | <command>cpio</command> is not installed by LFS.</para>
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280 | </listitem>
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281 | </varlistentry>
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282 |
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283 | <varlistentry>
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284 | <term>
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285 | <parameter>
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286 | Configure standard kernel features (expert users)
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287 | </parameter>
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288 | </term>
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289 | <listitem>
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290 | <para>This will make some options show up in the configuration
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291 | interface but changing those options may be dangerous. Do not use
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292 | this unless you know what you are doing.</para>
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293 | </listitem>
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294 | </varlistentry>
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295 |
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296 | <varlistentry>
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297 | <term><parameter>Strong Stack Protector</parameter></term>
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298 | <listitem>
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299 | <para>Enable SSP for the kernel. We've enabled it for the entire
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300 | userspace with <parameter>--enable-default-ssp</parameter>
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301 | configuring GCC, but the kernel does not use GCC default setting
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302 | for SSP. We enable it explicitly here.</para>
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303 | </listitem>
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304 | </varlistentry>
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305 |
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306 | <varlistentry>
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307 | <term><parameter>Support for uevent helper</parameter></term>
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308 | <listitem>
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309 | <para>Having this option set may interfere with device
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310 | management when using Udev/Eudev. </para>
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311 | </listitem>
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312 | </varlistentry>
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313 |
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314 | <varlistentry>
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315 | <term><parameter>Maintain a devtmpfs</parameter></term>
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316 | <listitem>
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317 | <para>This will create automated device nodes which are populated by the
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318 | kernel, even without Udev running. Udev then runs on top of this,
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319 | managing permissions and adding symlinks. This configuration
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320 | item is required for all users of Udev/Eudev.</para>
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321 | </listitem>
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322 | </varlistentry>
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323 |
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324 | <varlistentry>
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325 | <term><parameter>Automount devtmpfs at /dev</parameter></term>
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326 | <listitem>
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327 | <para>This will mount the kernel view of the devices on /dev
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328 | upon switching to root filesystem just before starting
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329 | init.</para>
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330 | </listitem>
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331 | </varlistentry>
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332 |
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333 | <varlistentry>
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334 | <term><parameter>Framebuffer Console support</parameter></term>
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335 | <listitem>
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336 | <para>This is needed to display the Linux console on a frame
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337 | buffer device. To allow the kernel to print debug messages at an
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338 | early boot stage, it shouldn't be built as a kernel module
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339 | unless an initramfs will be used. And, if
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340 | <option>CONFIG_DRM</option> (Direct Rendering Manager) is enabled,
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341 | it's likely <option>CONFIG_DRM_FBDEV_EMULATION</option> (Enable
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342 | legacy fbdev support for your modesetting driver) should be
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343 | enabled as well.</para>
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344 | </listitem>
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345 | </varlistentry>
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346 |
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347 | <varlistentry>
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348 | <term><parameter>Support x2apic</parameter></term>
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349 | <listitem>
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350 | <para>Support running the interrupt controller of 64-bit x86
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351 | processors in x2APIC mode. x2APIC may be enabled by firmware on
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352 | 64-bit x86 systems, and a kernel without this option enabled will
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353 | panic on boot if x2APIC is enabled by firmware. This option has
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354 | has no effect, but also does no harm if x2APIC is disabled by the
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355 | firmware.</para>
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356 | </listitem>
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357 | </varlistentry>
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358 |
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359 | </variablelist>
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360 |
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361 | <para>Alternatively, <command>make oldconfig</command> may be more
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362 | appropriate in some situations. See the <filename>README</filename>
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363 | file for more information.</para>
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364 |
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365 | <para>If desired, skip kernel configuration by copying the kernel
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366 | config file, <filename>.config</filename>, from the host system
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367 | (assuming it is available) to the unpacked <filename
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368 | class="directory">linux-&linux-version;</filename> directory. However,
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369 | we do not recommend this option. It is often better to explore all the
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370 | configuration menus and create the kernel configuration from
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371 | scratch.</para>
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372 |
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373 | <para>Compile the kernel image and modules:</para>
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374 |
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375 | <screen><userinput remap="make">make</userinput></screen>
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376 |
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377 | <para>If using kernel modules, module configuration in <filename
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378 | class="directory">/etc/modprobe.d</filename> may be required.
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379 | Information pertaining to modules and kernel configuration is
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380 | located in <xref linkend="ch-config-udev"/> and in the kernel
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381 | documentation in the <filename
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382 | class="directory">linux-&linux-version;/Documentation</filename> directory.
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383 | Also, <filename>modprobe.d(5)</filename> may be of interest.</para>
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384 |
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385 | <para>Unless module support has been disabled in the kernel configuration,
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386 | install the modules with:</para>
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387 |
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388 | <screen><userinput remap="install">make modules_install</userinput></screen>
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389 |
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390 | <para>After kernel compilation is complete, additional steps are
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391 | required to complete the installation. Some files need to be copied to
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392 | the <filename class="directory">/boot</filename> directory.</para>
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393 |
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394 | <caution>
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395 | <para>As the cross-built LFS system has a separate &boot-dir;
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396 | partition, the files copied below should go there. The easiest way to
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397 | do that is to create the entry for &boot-dir; in &fstab; first (read
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398 | the previous section for details), then issue the following command
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399 | as the &root; user:</para>
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400 |
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401 | <screen role="nodump"><userinput>mount /boot</userinput></screen>
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402 |
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403 | <para>We don't need to specify the path to the device node, as it's
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404 | already given in <filename>/etc/fstab</filename>.</para>
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405 | </caution>
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406 |
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407 | <para>The path to the kernel image may vary depending on the platform being
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408 | used. The filename below can be changed to suit your taste, but the stem of
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409 | the filename should be <emphasis>vmlinuz</emphasis> to be compatible with
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410 | the automatic setup of the boot process described in the next section. The
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411 | following command assumes an x86 architecture:</para>
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412 |
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413 | <screen><userinput remap="install">cp -iv arch/x86/boot/bzImage /boot/vmlinuz-&linux-version;-lfs-&version;</userinput></screen>
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414 |
|
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415 | <para><filename>System.map</filename> is a symbol file for the kernel.
|
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416 | It maps the function entry points of every function in the kernel API,
|
---|
417 | as well as the addresses of the kernel data structures for the running
|
---|
418 | kernel. It is used as a resource when investigating kernel problems.
|
---|
419 | Issue the following command to install the map file:</para>
|
---|
420 |
|
---|
421 | <screen><userinput remap="install">cp -iv System.map /boot/System.map-&linux-version;</userinput></screen>
|
---|
422 |
|
---|
423 | <para>The kernel configuration file <filename>.config</filename>
|
---|
424 | produced by the <command>make menuconfig</command> step
|
---|
425 | above contains all the configuration selections for the kernel
|
---|
426 | that was just compiled. It is a good idea to keep this file for future
|
---|
427 | reference:</para>
|
---|
428 |
|
---|
429 | <screen><userinput remap="install">cp -iv .config /boot/config-&linux-version;</userinput></screen>
|
---|
430 |
|
---|
431 | <para>Install the documentation for the Linux kernel:</para>
|
---|
432 |
|
---|
433 | <screen><userinput remap="install">install -d /usr/share/doc/linux-&linux-version;
|
---|
434 | cp -r Documentation/* /usr/share/doc/linux-&linux-version;</userinput></screen>
|
---|
435 |
|
---|
436 | <para>It is important to note that the files in the kernel source
|
---|
437 | directory are not owned by <emphasis>root</emphasis>. Whenever a
|
---|
438 | package is unpacked as user <emphasis>root</emphasis> (like we did
|
---|
439 | inside chroot), the files have the user and group IDs of whatever
|
---|
440 | they were on the packager's computer. This is usually not a problem
|
---|
441 | for any other package to be installed because the source tree is
|
---|
442 | removed after the installation. However, the Linux source tree is
|
---|
443 | often retained for a long time. Because of this, there is a chance
|
---|
444 | that whatever user ID the packager used will be assigned to somebody
|
---|
445 | on the machine. That person would then have write access to the kernel
|
---|
446 | source.</para>
|
---|
447 |
|
---|
448 | <note>
|
---|
449 | <para>In many cases, the configuration of the kernel will need to be
|
---|
450 | updated for packages that will be installed later in BLFS. Unlike
|
---|
451 | other packages, it is not necessary to remove the kernel source tree
|
---|
452 | after the newly built kernel is installed.</para>
|
---|
453 |
|
---|
454 | <para>If the kernel source tree is going to be retained, run
|
---|
455 | <command>chown -R 0:0</command> on the <filename
|
---|
456 | class="directory">linux-&linux-version;</filename> directory to ensure
|
---|
457 | all files are owned by user <emphasis>root</emphasis>.</para>
|
---|
458 | </note>
|
---|
459 |
|
---|
460 | <warning>
|
---|
461 | <para>Some kernel documentation recommends creating a symlink from
|
---|
462 | <filename class="symlink">/usr/src/linux</filename> pointing to the kernel
|
---|
463 | source directory. This is specific to kernels prior to the 2.6 series and
|
---|
464 | <emphasis>must not</emphasis> be created on an LFS system as it can cause
|
---|
465 | problems for packages you may wish to build once your base LFS system is
|
---|
466 | complete.</para>
|
---|
467 | </warning>
|
---|
468 |
|
---|
469 | <warning>
|
---|
470 | <para>The headers in the system's <filename
|
---|
471 | class="directory">include</filename> directory (<filename
|
---|
472 | class="directory">/usr/include</filename>) should
|
---|
473 | <emphasis>always</emphasis> be the ones against which Glibc was compiled,
|
---|
474 | that is, the sanitised headers installed in <xref
|
---|
475 | linkend="ch-tools-linux-headers"/>. Therefore, they should
|
---|
476 | <emphasis>never</emphasis> be replaced by either the raw kernel headers
|
---|
477 | or any other kernel sanitized headers.</para>
|
---|
478 | </warning>
|
---|
479 |
|
---|
480 | </sect2>
|
---|
481 |
|
---|
482 | <sect2 id="conf-modprobe" role="configuration">
|
---|
483 | <title>Configuring Linux Module Load Order</title>
|
---|
484 |
|
---|
485 | <indexterm zone="conf-modprobe">
|
---|
486 | <primary sortas="e-/etc/modprobe.d/usb.conf">/etc/modprobe.d/usb.conf</primary>
|
---|
487 | </indexterm>
|
---|
488 |
|
---|
489 | <para>Most of the time Linux modules are loaded automatically, but
|
---|
490 | sometimes it needs some specific direction. The program that loads
|
---|
491 | modules, <command>modprobe</command> or <command>insmod</command>, uses
|
---|
492 | <filename>/etc/modprobe.d/usb.conf</filename> for this purpose. This file
|
---|
493 | needs to be created so that if the USB drivers (ehci_hcd, ohci_hcd and
|
---|
494 | uhci_hcd) have been built as modules, they will be loaded in the correct
|
---|
495 | order; ehci_hcd needs to be loaded prior to ohci_hcd and uhci_hcd in order
|
---|
496 | to avoid a warning being output at boot time.</para>
|
---|
497 |
|
---|
498 | <para>Create a new file <filename>/etc/modprobe.d/usb.conf</filename> by running
|
---|
499 | the following:</para>
|
---|
500 |
|
---|
501 | <screen><userinput>install -v -m755 -d /etc/modprobe.d
|
---|
502 | cat > /etc/modprobe.d/usb.conf << "EOF"
|
---|
503 | <literal># Begin /etc/modprobe.d/usb.conf
|
---|
504 |
|
---|
505 | install ohci_hcd /sbin/modprobe ehci_hcd ; /sbin/modprobe -i ohci_hcd ; true
|
---|
506 | install uhci_hcd /sbin/modprobe ehci_hcd ; /sbin/modprobe -i uhci_hcd ; true
|
---|
507 |
|
---|
508 | # End /etc/modprobe.d/usb.conf</literal>
|
---|
509 | EOF</userinput></screen>
|
---|
510 |
|
---|
511 | </sect2>
|
---|
512 |
|
---|
513 | <sect2 id="contents-kernel" role="content">
|
---|
514 | <title>Contents of Linux</title>
|
---|
515 |
|
---|
516 | <segmentedlist>
|
---|
517 | <segtitle>Installed files</segtitle>
|
---|
518 | <segtitle>Installed directories</segtitle>
|
---|
519 |
|
---|
520 | <seglistitem>
|
---|
521 | <seg>config-&linux-version;,
|
---|
522 | vmlinuz-&linux-version;-lfs-&version;,
|
---|
523 | and System.map-&linux-version;</seg>
|
---|
524 | <seg>/lib/modules, /usr/share/doc/linux-&linux-version;</seg>
|
---|
525 | </seglistitem>
|
---|
526 | </segmentedlist>
|
---|
527 |
|
---|
528 | <variablelist>
|
---|
529 | <bridgehead renderas="sect3">Short Descriptions</bridgehead>
|
---|
530 | <?dbfo list-presentation="list"?>
|
---|
531 | <?dbhtml list-presentation="table"?>
|
---|
532 |
|
---|
533 | <varlistentry id="config">
|
---|
534 | <term><filename>config-&linux-version;</filename></term>
|
---|
535 | <listitem>
|
---|
536 | <para>Contains all the configuration selections for the kernel</para>
|
---|
537 | <indexterm zone="ch-bootable-kernel config">
|
---|
538 | <primary sortas="e-/boot/config">/boot/config-&linux-version;</primary>
|
---|
539 | </indexterm>
|
---|
540 | </listitem>
|
---|
541 | </varlistentry>
|
---|
542 |
|
---|
543 | <varlistentry id="lfskernel">
|
---|
544 | <term><filename>vmlinuz-&linux-version;-lfs-&version;</filename></term>
|
---|
545 | <listitem>
|
---|
546 | <para>The engine of the Linux system. When turning on the computer,
|
---|
547 | the kernel is the first part of the operating system that gets loaded.
|
---|
548 | It detects and initializes all components of the computer's hardware,
|
---|
549 | then makes these components available as a tree of files to the
|
---|
550 | software and turns a single CPU into a multitasking machine capable
|
---|
551 | of running scores of programs seemingly at the same time</para>
|
---|
552 | <indexterm zone="ch-bootable-kernel lfskernel">
|
---|
553 | <primary sortas="b-lfskernel">lfskernel-&linux-version;</primary>
|
---|
554 | </indexterm>
|
---|
555 | </listitem>
|
---|
556 | </varlistentry>
|
---|
557 |
|
---|
558 | <varlistentry id="System.map">
|
---|
559 | <term><filename>System.map-&linux-version;</filename></term>
|
---|
560 | <listitem>
|
---|
561 | <para>A list of addresses and symbols; it maps the entry points and
|
---|
562 | addresses of all the functions and data structures in the
|
---|
563 | kernel</para>
|
---|
564 | <indexterm zone="ch-bootable-kernel System.map">
|
---|
565 | <primary sortas="e-/boot/System.map">/boot/System.map-&linux-version;</primary>
|
---|
566 | </indexterm>
|
---|
567 | </listitem>
|
---|
568 | </varlistentry>
|
---|
569 |
|
---|
570 | </variablelist>
|
---|
571 |
|
---|
572 | </sect2>
|
---|
573 |
|
---|
574 | </sect1>
|
---|