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1	<?xml version="1.0" encoding="ISO-8859-1"?>
2	<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3	"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
4	<!ENTITY % general-entities SYSTEM "../general.ent">
5	%general-entities;
6	]>
7
8	<sect1 id="ch-bootable-kernel" role="wrap">
9	<?dbhtml filename="kernel.html"?>
10
11	<sect1info condition="script">
12	<productname>kernel</productname>
13	<productnumber>&linux-version;</productnumber>
14	<address>&linux-url;</address>
15	</sect1info>
16
17	<title>Linux-&linux-version;</title>
18
19	<indexterm zone="ch-bootable-kernel">
20	<primary sortas="a-Linux">Linux</primary>
21	</indexterm>
22
23	<sect2 role="package">
24	<title/>
25
26	<para>The Linux package contains the Linux kernel.</para>
27
28	<segmentedlist>
29	<segtitle>&buildtime;</segtitle>
30	<segtitle>&diskspace;</segtitle>
31
32	<seglistitem>
33	<seg>&linux-knl-sbu;</seg>
34	<seg>&linux-knl-du;</seg>
35	</seglistitem>
36	</segmentedlist>
37
38	</sect2>
39
40	<sect2 role="installation">
41	<title>Installation of the kernel</title>
42
43	<para>Building the kernel involves a few steps—configuration,
44	compilation, and installation. Read the <filename>README</filename> file
45	in the kernel source tree for alternative methods to the way this book
46	configures the kernel.</para>
47
48	<important>
49	<para>
50	Building the linux kernel for the first time is one of the most
51	challenging tasks in LFS. Getting it right depends on the specific
52	hardware for the target system and your specific needs. There are
53	almost 12,000 configuration items that are available for the kernel
54	although only about a third of them are needed for most computers. The
55	LFS editors recommend that users not familiar with this process follow
56	the procedures below fairly closely. The objective is to get an
57	initial system to a point where you can log in at the command line when
58	you reboot later in <xref linkend="ch-finish-reboot"/>. At his point
59	optimization and customization is not a goal.
60	</para>
61
62
63	<para>
64	For general information on kernel configuration see <ulink
65	url="&hints-root;kernel-configuration.txt"/>. Additional information
66	about configuring and building the kernel can be found at <ulink
67	url="&anduin-sources;/kernel-nutshell/"/>.
68	These references are a bit
69	dated, but still give a reasonable overview of the process.
70	</para>
71
72	<para>
73	If all else fails, you can ask for help on the <ulink
74	url="https://www.linuxfromscratch.org/mail.html">lfs-support</ulink>
75	mailing list. Note that subscribing is required in order for the list
76	to avoid spam.
77	</para>
78	</important>
79
80	<para>Prepare for compilation by running the following command:</para>
81
82	<screen><userinput remap="pre">make mrproper</userinput></screen>
83
84	<para>This ensures that the kernel tree is absolutely clean. The
85	kernel team recommends that this command be issued prior to each
86	kernel compilation. Do not rely on the source tree being clean after
87	un-tarring.</para>
88
89	<para>There are several ways to configure the kernel options. Usually,
90	This is done through a menu-driven interface, for example:</para>
91
92	<screen role="nodump"><userinput>make menuconfig</userinput></screen>
93
94	<variablelist>
95	<title>The meaning of optional make environment variables:</title>
96
97	<varlistentry>
98	<term><parameter>LANG=<host_LANG_value> LC_ALL=</parameter></term>
99	<listitem>
100	<para>This establishes the locale setting to the one used on the
101	host. This may be needed for a proper menuconfig ncurses interface
102	line drawing on a UTF-8 linux text console.</para>
103
104	<para>If used, be sure to replace
105	<replaceable><host_LANG_value></replaceable> by the value of
106	the <envar>$LANG</envar> variable from your host. You can
107	alternatively use instead the host's value of <envar>$LC_ALL</envar>
108	or <envar>$LC_CTYPE</envar>.</para>
109	</listitem>
110	</varlistentry>
111
112	<varlistentry>
113	<term><command>make menuconfig</command></term>
114	<listitem>
115	<para>This launches an ncurses menu-driven interface. For other
116	(graphical) interfaces, type <command>make help</command>.</para>
117	</listitem>
118	</varlistentry>
119	</variablelist>
120
121	<!-- Support for compiling a keymap into the kernel is deliberately removed -->
122
123
124	<note>
125	<para>A good starting place for setting up the kernel configuration is to
126	run <command>make defconfig</command>. This will set the base
127	configuration to a good state that takes your current system architecture
128	into account.</para>
129
130	<para>Be sure to enable/disable/set the following features or the system might
131	not work correctly or boot at all:</para>
132
133	<screen role="nodump" revision="sysv">Processor type and features --->
134	[*] Build a relocatable kernel [CONFIG_RELOCATABLE]
135	[*] Randomize the address of the kernel image (KASLR) [CONFIG_RANDOMIZE_BASE]
136	General setup --->
137	[ ] Compile the kernel with warnings as errors [CONFIG_WERROR]
138	< > Enable kernel headers through /sys/kernel/kheaders.tar.xz [CONFIG_IKHEADERS]
139	[ ] Configure standard kernel features (expert users) [CONFIG_EXPERT]
140	General architecture-dependent options --->
141	[*] Stack Protector buffer overflow detection [CONFIG_STACKPROTECTOR]
142	[*] Strong Stack Protector [CONFIG_STACKPROTECTOR_STRONG]
143	Device Drivers --->
144	Graphics support --->
145	Frame buffer Devices --->
146	<*> Support for frame buffer devices --->
147	Console display driver support --->
148	[*] Framebuffer Console support [CONFIG_FRAMEBUFFER_CONSOLE]
149	Generic Driver Options --->
150	[ ] Support for uevent helper [CONFIG_UEVENT_HELPER]
151	[*] Maintain a devtmpfs filesystem to mount at /dev [CONFIG_DEVTMPFS]
152	[*] Automount devtmpfs at /dev, after the kernel mounted the rootfs [CONFIG_DEVTMPFS_MOUNT]</screen>
153
154	<screen role="nodump" revision="systemd">Processor type and features --->
155	[*] Build a relocatable kernel [CONFIG_RELOCATABLE]
156	[*] Randomize the address of the kernel image (KASLR) [CONFIG_RANDOMIZE_BASE]
157	General setup --->
158	[ ] Compile the kernel with warnings as errors [CONFIG_WERROR]
159	[ ] Auditing Support [CONFIG_AUDIT]
160	CPU/Task time and stats accounting --->
161	[*] Pressure stall information tracking [CONFIG_PSI]
162	[ ] Require boot parameter to enable pressure stall information tracking [CONFIG_PSI_DEFAULT_DISABLED]
163	< > Enable kernel headers through /sys/kernel/kheaders.tar.xz [CONFIG_IKHEADERS]
164	[*] Control Group support [CONFIG_CGROUPS] --->
165	[*] Memory controller [CONFIG_MEMCG]
166	[ ] Enable deprecated sysfs features to support old userspace tools [CONFIG_SYSFS_DEPRECATED]
167	[ ] Configure standard kernel features (expert users) [CONFIG_EXPERT]
168	General architecture-dependent options --->
169	[*] Enable seccomp to safely compute untrusted bytecode [CONFIG_SECCOMP]
170	[*] Stack Protector buffer overflow detection [CONFIG_STACKPROTECTOR]
171	[*] Strong Stack Protector [CONFIG_STACKPROTECTOR_STRONG]
172	[*] Networking support ---> [CONFIG_NET]
173	Networking options --->
174	[*] TCP/IP networking [CONFIG_INET]
175	<*> The IPv6 protocol [CONFIG_IPV6]
176	Device Drivers --->
177	Generic Driver Options --->
178	[ ] Support for uevent helper [CONFIG_UEVENT_HELPER]
179	[*] Maintain a devtmpfs filesystem to mount at /dev [CONFIG_DEVTMPFS]
180	[*] Automount devtmpfs at /dev, after the kernel mounted the rootfs [CONFIG_DEVTMPFS_MOUNT]
181	Firmware Loader --->
182	[ ] Enable the firmware sysfs fallback mechanism [CONFIG_FW_LOADER_USER_HELPER]
183	Firmware Drivers --->
184	[*] Export DMI identification via sysfs to userspace [CONFIG_DMIID]
185	Graphics support --->
186	Frame buffer Devices --->
187	<*> Support for frame buffer devices --->
188	Console display driver support --->
189	[*] Framebuffer Console support [CONFIG_FRAMEBUFFER_CONSOLE]
190	File systems --->
191	[*] Inotify support for userspace [CONFIG_INOTIFY_USER]
192	Pseudo filesystems --->
193	[*] Tmpfs POSIX Access Control Lists [CONFIG_TMPFS_POSIX_ACL]</screen>
194
195	<para>Enable some additional features if you are building a 64-bit
196	system. If you are using menuconfig, enable them in the order of
197	<parameter>CONFIG_PCI_MSI</parameter> first, then
198	<parameter>CONFIG_IRQ_REMAP</parameter>, at last
199	<parameter>CONFIG_X86_X2APIC</parameter> because an option only
200	shows up after its dependencies are selected.</para>
201
202	<screen role="nodump">Processor type and features --->
203	[*] Support x2apic [CONFIG_X86_X2APIC]
204	Device Drivers --->
205	[*] PCI Support ---> [CONFIG_PCI]
206	[*] Message Signaled Interrupts (MSI and MSI-X) [CONFIG_PCI_MSI]
207	[*] IOMMU Hardware Support ---> [CONFIG_IOMMU_SUPPORT]
208	[*] Support for Interrupt Remapping [CONFIG_IRQ_REMAP]</screen>
209
210	<para>If you are building a 32-bit system running on a hardware
211	with RAM more than 4GB, adjust the configuration so the kernel will
212	be able to use up to 64GB physical RAM:</para>
213
214	<screen role="nodump">Processor type and features --->
215	High Memory Support --->
216	(X) 64GB [CONFIG_HIGHMEM64G]</screen>
217
218	<para>If the partition for the LFS system is in a NVME SSD (i. e. the
219	device node for the partition is <filename>/dev/nvme*</filename>
220	instead of <filename>/dev/sd*</filename>), enable NVME support or
221	the LFS system won't boot:</para>
222
223	<screen role="nodump">Device Drivers --->
224	NVME Support --->
225	<*> NVM Express block device [CONFIG_BLK_DEV_NVME]</screen>
226	</note>
227
228	<note revision="systemd">
229	<para>While "The IPv6 Protocol" is not strictly
230	required, it is highly recommended by the systemd developers.</para>
231	</note>
232
233	<para>There are several other options that may be desired
234	depending on the requirements for the system. For a list of options needed
235	for BLFS packages, see the <ulink
236	url="&lfs-root;blfs/view/&short-version;/longindex.html#kernel-config-index">BLFS
237	Index of Kernel Settings</ulink>.</para>
238
239	<note>
240	<para>If your host hardware is using UEFI and you wish to boot the
241	LFS system with it, you should adjust some kernel configuration
242	following <ulink url="&blfs-book;postlfs/grub-setup.html#uefi-kernel">
243	the BLFS page</ulink> <emphasis role='bold'>even if you'll use the
244	UEFI bootloader from the host distro</emphasis>.</para>
245	</note>
246
247	<note arch="ml_32,ml_x32,ml_all">
248	<para>
249	The kernel on a multilib system needs to be able to
250	identify and start binaries compiled for different architectures
251	than the default.
252	</para>
253
254	<para arch="ml_32,ml_all">
255	If support for any 32bit ABI was built, make sure that the option
256	"IA32 Emulation" is selected. The option 'IA32 a.out support' is
257	optional.
258	</para>
259
260	<para arch="ml_x32,ml_all">
261	If support for the x32bit ABI was built, make sure that the option
262	"x32 ABI for 64-bit mode" is selected.
263	</para>
264
265	<screen arch="ml_32">Binary Emulations --->
266	[*] IA32 Emulation [CONFIG_IA32_EMULATION]
267	<M> IA32 a.out support [CONFIG_IA32_AOUT]
268	</screen>
269	<screen arch="ml_x32">Binary Emulations --->
270	[*] x32 ABI for 64-bit mode [CONFIG_X86_X32]
271	</screen>
272	<screen arch="ml_all">Binary Emulations --->
273	[*] IA32 Emulation [CONFIG_IA32_EMULATION]
274	<M> IA32 a.out support [CONFIG_IA32_AOUT]
275	[*] x32 ABI for 64-bit mode [CONFIG_X86_X32]
276	</screen>
277	</note>
278
279	<variablelist>
280	<title>The rationale for the above configuration items:</title>
281
282	<varlistentry>
283	<term><parameter>Randomize the address of the kernel image (KASLR)</parameter></term>
284	<listitem>
285	<para>Enable ASLR for kernel image, to mitigate some attacks based
286	on fixed addresses of sensitive data or code in the kernel.</para>
287	</listitem>
288	</varlistentry>
289
290	<varlistentry>
291	<term>
292	<parameter>
293	Compile the kernel with warnings as errors
294	</parameter>
295	</term>
296	<listitem>
297	<para>This may cause building failure if the compiler and/or
298	configuration are different from those of the kernel
299	developers.</para>
300	</listitem>
301	</varlistentry>
302
303	<varlistentry>
304	<term>
305	<parameter>
306	Enable kernel headers through /sys/kernel/kheaders.tar.xz
307	</parameter>
308	</term>
309	<listitem>
310	<para>This will require <command>cpio</command> building the kernel.
311	<command>cpio</command> is not installed by LFS.</para>
312	</listitem>
313	</varlistentry>
314
315	<varlistentry>
316	<term>
317	<parameter>
318	Configure standard kernel features (expert users)
319	</parameter>
320	</term>
321	<listitem>
322	<para>This will make some options show up in the configuration
323	interface but changing those options may be dangerous. Do not use
324	this unless you know what you are doing.</para>
325	</listitem>
326	</varlistentry>
327
328	<varlistentry>
329	<term><parameter>Strong Stack Protector</parameter></term>
330	<listitem>
331	<para>Enable SSP for the kernel. We've enabled it for the entire
332	userspace with <parameter>--enable-default-ssp</parameter>
333	configuring GCC, but the kernel does not use GCC default setting
334	for SSP. We enable it explicitly here.</para>
335	</listitem>
336	</varlistentry>
337
338	<varlistentry>
339	<term><parameter>Support for uevent helper</parameter></term>
340	<listitem>
341	<para>Having this option set may interfere with device
342	management when using Udev/Eudev. </para>
343	</listitem>
344	</varlistentry>
345
346	<varlistentry>
347	<term><parameter>Maintain a devtmpfs</parameter></term>
348	<listitem>
349	<para>This will create automated device nodes which are populated by the
350	kernel, even without Udev running. Udev then runs on top of this,
351	managing permissions and adding symlinks. This configuration
352	item is required for all users of Udev/Eudev.</para>
353	</listitem>
354	</varlistentry>
355
356	<varlistentry>
357	<term><parameter>Automount devtmpfs at /dev</parameter></term>
358	<listitem>
359	<para>This will mount the kernel view of the devices on /dev
360	upon switching to root filesystem just before starting
361	init.</para>
362	</listitem>
363	</varlistentry>
364
365	<varlistentry>
366	<term><parameter>Framebuffer Console support</parameter></term>
367	<listitem>
368	<para>This is needed to display the Linux console on a frame
369	buffer device. To allow the kernel to print debug messages at an
370	early boot stage, it shouldn't be built as a kernel module
371	unless an initramfs will be used. And, if
372	<option>CONFIG_DRM</option> (Direct Rendering Manager) is enabled,
373	it's likely <option>CONFIG_DRM_FBDEV_EMULATION</option> (Enable
374	legacy fbdev support for your modesetting driver) should be
375	enabled as well.</para>
376	</listitem>
377	</varlistentry>
378
379	<varlistentry>
380	<term><parameter>Support x2apic</parameter></term>
381	<listitem>
382	<para>Support running the interrupt controller of 64-bit x86
383	processors in x2APIC mode. x2APIC may be enabled by firmware on
384	64-bit x86 systems, and a kernel without this option enabled will
385	panic on boot if x2APIC is enabled by firmware. This option has
386	has no effect, but also does no harm if x2APIC is disabled by the
387	firmware.</para>
388	</listitem>
389	</varlistentry>
390
391	</variablelist>
392
393	<para>Alternatively, <command>make oldconfig</command> may be more
394	appropriate in some situations. See the <filename>README</filename>
395	file for more information.</para>
396
397	<para>If desired, skip kernel configuration by copying the kernel
398	config file, <filename>.config</filename>, from the host system
399	(assuming it is available) to the unpacked <filename
400	class="directory">linux-&linux-version;</filename> directory. However,
401	we do not recommend this option. It is often better to explore all the
402	configuration menus and create the kernel configuration from
403	scratch.</para>
404
405	<para>Compile the kernel image and modules:</para>
406
407	<screen><userinput remap="make">make</userinput></screen>
408
409	<para>If using kernel modules, module configuration in <filename
410	class="directory">/etc/modprobe.d</filename> may be required.
411	Information pertaining to modules and kernel configuration is
412	located in <xref linkend="ch-config-udev"/> and in the kernel
413	documentation in the <filename
414	class="directory">linux-&linux-version;/Documentation</filename> directory.
415	Also, <filename>modprobe.d(5)</filename> may be of interest.</para>
416
417	<para>Unless module support has been disabled in the kernel configuration,
418	install the modules with:</para>
419
420	<screen><userinput remap="install">make modules_install</userinput></screen>
421
422	<para>After kernel compilation is complete, additional steps are
423	required to complete the installation. Some files need to be copied to
424	the <filename class="directory">/boot</filename> directory.</para>
425
426	<caution>
427	<para>If you've decided to use a separate &boot-dir; partition for the
428	LFS system (maybe sharing a &boot-dir; partition with the host
429	distro) , the files copied below should go there. The easiest way to
430	do that is to create the entry for &boot-dir; in &fstab; first (read
431	the previous section for details), then issue the following command
432	as the &root; user in the
433	<emphasis>chroot environment</emphasis>:</para>
434
435	<screen role="nodump"><userinput>mount /boot</userinput></screen>
436
437	<para>The path to the device node is omitted in the command because
438	<command>mount</command> can read it from &fstab;.</para>
439	</caution>
440
441	<para>The path to the kernel image may vary depending on the platform being
442	used. The filename below can be changed to suit your taste, but the stem of
443	the filename should be <emphasis>vmlinuz</emphasis> to be compatible with
444	the automatic setup of the boot process described in the next section. The
445	following command assumes an x86 architecture:</para>
446
447	<screen><userinput remap="install">cp -iv arch/x86/boot/bzImage /boot/vmlinuz-&linux-version;-lfs-&version;</userinput></screen>
448
449	<para><filename>System.map</filename> is a symbol file for the kernel.
450	It maps the function entry points of every function in the kernel API,
451	as well as the addresses of the kernel data structures for the running
452	kernel. It is used as a resource when investigating kernel problems.
453	Issue the following command to install the map file:</para>
454
455	<screen><userinput remap="install">cp -iv System.map /boot/System.map-&linux-version;</userinput></screen>
456
457	<para>The kernel configuration file <filename>.config</filename>
458	produced by the <command>make menuconfig</command> step
459	above contains all the configuration selections for the kernel
460	that was just compiled. It is a good idea to keep this file for future
461	reference:</para>
462
463	<screen><userinput remap="install">cp -iv .config /boot/config-&linux-version;</userinput></screen>
464
465	<para>Install the documentation for the Linux kernel:</para>
466
467	<screen><userinput remap="install">install -d /usr/share/doc/linux-&linux-version;
468	cp -r Documentation/* /usr/share/doc/linux-&linux-version;</userinput></screen>
469
470	<para>It is important to note that the files in the kernel source
471	directory are not owned by <emphasis>root</emphasis>. Whenever a
472	package is unpacked as user <emphasis>root</emphasis> (like we did
473	inside chroot), the files have the user and group IDs of whatever
474	they were on the packager's computer. This is usually not a problem
475	for any other package to be installed because the source tree is
476	removed after the installation. However, the Linux source tree is
477	often retained for a long time. Because of this, there is a chance
478	that whatever user ID the packager used will be assigned to somebody
479	on the machine. That person would then have write access to the kernel
480	source.</para>
481
482	<note>
483	<para>In many cases, the configuration of the kernel will need to be
484	updated for packages that will be installed later in BLFS. Unlike
485	other packages, it is not necessary to remove the kernel source tree
486	after the newly built kernel is installed.</para>
487
488	<para>If the kernel source tree is going to be retained, run
489	<command>chown -R 0:0</command> on the <filename
490	class="directory">linux-&linux-version;</filename> directory to ensure
491	all files are owned by user <emphasis>root</emphasis>.</para>
492	</note>
493
494	<warning>
495	<para>Some kernel documentation recommends creating a symlink from
496	<filename class="symlink">/usr/src/linux</filename> pointing to the kernel
497	source directory. This is specific to kernels prior to the 2.6 series and
498	<emphasis>must not</emphasis> be created on an LFS system as it can cause
499	problems for packages you may wish to build once your base LFS system is
500	complete.</para>
501	</warning>
502
503	<warning>
504	<para>The headers in the system's <filename
505	class="directory">include</filename> directory (<filename
506	class="directory">/usr/include</filename>) should
507	<emphasis>always</emphasis> be the ones against which Glibc was compiled,
508	that is, the sanitised headers installed in <xref
509	linkend="ch-tools-linux-headers"/>. Therefore, they should
510	<emphasis>never</emphasis> be replaced by either the raw kernel headers
511	or any other kernel sanitized headers.</para>
512	</warning>
513
514	</sect2>
515
516	<sect2 id="conf-modprobe" role="configuration">
517	<title>Configuring Linux Module Load Order</title>
518
519	<indexterm zone="conf-modprobe">
520	<primary sortas="e-/etc/modprobe.d/usb.conf">/etc/modprobe.d/usb.conf</primary>
521	</indexterm>
522
523	<para>Most of the time Linux modules are loaded automatically, but
524	sometimes it needs some specific direction. The program that loads
525	modules, <command>modprobe</command> or <command>insmod</command>, uses
526	<filename>/etc/modprobe.d/usb.conf</filename> for this purpose. This file
527	needs to be created so that if the USB drivers (ehci_hcd, ohci_hcd and
528	uhci_hcd) have been built as modules, they will be loaded in the correct
529	order; ehci_hcd needs to be loaded prior to ohci_hcd and uhci_hcd in order
530	to avoid a warning being output at boot time.</para>
531
532	<para>Create a new file <filename>/etc/modprobe.d/usb.conf</filename> by running
533	the following:</para>
534
535	<screen><userinput>install -v -m755 -d /etc/modprobe.d
536	cat > /etc/modprobe.d/usb.conf << "EOF"
537	<literal># Begin /etc/modprobe.d/usb.conf
538
539	install ohci_hcd /sbin/modprobe ehci_hcd ; /sbin/modprobe -i ohci_hcd ; true
540	install uhci_hcd /sbin/modprobe ehci_hcd ; /sbin/modprobe -i uhci_hcd ; true
541
542	# End /etc/modprobe.d/usb.conf</literal>
543	EOF</userinput></screen>
544
545	</sect2>
546
547	<sect2 id="contents-kernel" role="content">
548	<title>Contents of Linux</title>
549
550	<segmentedlist>
551	<segtitle>Installed files</segtitle>
552	<segtitle>Installed directories</segtitle>
553
554	<seglistitem>
555	<seg>config-&linux-version;,
556	vmlinuz-&linux-version;-lfs-&version;,
557	and System.map-&linux-version;</seg>
558	<seg>/lib/modules, /usr/share/doc/linux-&linux-version;</seg>
559	</seglistitem>
560	</segmentedlist>
561
562	<variablelist>
563	<bridgehead renderas="sect3">Short Descriptions</bridgehead>
564	<?dbfo list-presentation="list"?>
565	<?dbhtml list-presentation="table"?>
566
567	<varlistentry id="config">
568	<term><filename>config-&linux-version;</filename></term>
569	<listitem>
570	<para>Contains all the configuration selections for the kernel</para>
571	<indexterm zone="ch-bootable-kernel config">
572	<primary sortas="e-/boot/config">/boot/config-&linux-version;</primary>
573	</indexterm>
574	</listitem>
575	</varlistentry>
576
577	<varlistentry id="lfskernel">
578	<term><filename>vmlinuz-&linux-version;-lfs-&version;</filename></term>
579	<listitem>
580	<para>The engine of the Linux system. When turning on the computer,
581	the kernel is the first part of the operating system that gets loaded.
582	It detects and initializes all components of the computer's hardware,
583	then makes these components available as a tree of files to the
584	software and turns a single CPU into a multitasking machine capable
585	of running scores of programs seemingly at the same time</para>
586	<indexterm zone="ch-bootable-kernel lfskernel">
587	<primary sortas="b-lfskernel">lfskernel-&linux-version;</primary>
588	</indexterm>
589	</listitem>
590	</varlistentry>
591
592	<varlistentry id="System.map">
593	<term><filename>System.map-&linux-version;</filename></term>
594	<listitem>
595	<para>A list of addresses and symbols; it maps the entry points and
596	addresses of all the functions and data structures in the
597	kernel</para>
598	<indexterm zone="ch-bootable-kernel System.map">
599	<primary sortas="e-/boot/System.map">/boot/System.map-&linux-version;</primary>
600	</indexterm>
601	</listitem>
602	</varlistentry>
603
604	</variablelist>
605
606	</sect2>
607
608	</sect1>

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