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1.. _changes:
2
3Minimal requirements to compile the Kernel
4++++++++++++++++++++++++++++++++++++++++++
5
6Intro
7=====
8
9This document is designed to provide a list of the minimum levels of
10software necessary to run the current kernel version.
11
12This document is originally based on my "Changes" file for 2.0.x kernels
13and therefore owes credit to the same people as that file (Jared Mauch,
14Axel Boldt, Alessandro Sigala, and countless other users all over the
15'net).
16
17Current Minimal Requirements
18****************************
19
20Upgrade to at **least** these software revisions before thinking you've
21encountered a bug! If you're unsure what version you're currently
22running, the suggested command should tell you.
23
24Again, keep in mind that this list assumes you are already functionally
25running a Linux kernel. Also, not all tools are necessary on all
26systems; obviously, if you don't have any PC Card hardware, for example,
27you probably needn't concern yourself with pcmciautils.
28
29====================== =============== ========================================
30 Program Minimal version Command to check the version
31====================== =============== ========================================
32GNU C 5.1 gcc --version
33Clang/LLVM (optional) 13.0.1 clang --version
34Rust (optional) 1.78.0 rustc --version
35bindgen (optional) 0.65.1 bindgen --version
36GNU make 4.0 make --version
37bash 4.2 bash --version
38binutils 2.25 ld -v
39flex 2.5.35 flex --version
40bison 2.0 bison --version
41pahole 1.16 pahole --version
42util-linux 2.10o mount --version
43kmod 13 depmod -V
44e2fsprogs 1.41.4 e2fsck -V
45jfsutils 1.1.3 fsck.jfs -V
46reiserfsprogs 3.6.3 reiserfsck -V
47xfsprogs 2.6.0 xfs_db -V
48squashfs-tools 4.0 mksquashfs -version
49btrfs-progs 0.18 btrfs --version
50pcmciautils 004 pccardctl -V
51quota-tools 3.09 quota -V
52PPP 2.4.0 pppd --version
53nfs-utils 1.0.5 showmount --version
54procps 3.2.0 ps --version
55udev 081 udevd --version
56grub 0.93 grub --version || grub-install --version
57mcelog 0.6 mcelog --version
58iptables 1.4.2 iptables -V
59openssl & libcrypto 1.0.0 openssl version
60bc 1.06.95 bc --version
61Sphinx\ [#f1]_ 2.4.4 sphinx-build --version
62cpio any cpio --version
63GNU tar 1.28 tar --version
64gtags (optional) 6.6.5 gtags --version
65mkimage (optional) 2017.01 mkimage --version
66Python (optional) 3.5.x python3 --version
67GNU AWK (optional) 5.1.0 gawk --version
68====================== =============== ========================================
69
70.. [#f1] Sphinx is needed only to build the Kernel documentation
71
72Kernel compilation
73******************
74
75GCC
76---
77
78The gcc version requirements may vary depending on the type of CPU in your
79computer.
80
81Clang/LLVM (optional)
82---------------------
83
84The latest formal release of clang and LLVM utils (according to
85`releases.llvm.org <https://releases.llvm.org>`_) are supported for building
86kernels. Older releases aren't guaranteed to work, and we may drop workarounds
87from the kernel that were used to support older versions. Please see additional
88docs on :ref:`Building Linux with Clang/LLVM <kbuild_llvm>`.
89
90Rust (optional)
91---------------
92
93A recent version of the Rust compiler is required.
94
95Please see Documentation/rust/quick-start.rst for instructions on how to
96satisfy the build requirements of Rust support. In particular, the ``Makefile``
97target ``rustavailable`` is useful to check why the Rust toolchain may not
98be detected.
99
100bindgen (optional)
101------------------
102
103``bindgen`` is used to generate the Rust bindings to the C side of the kernel.
104It depends on ``libclang``.
105
106Make
107----
108
109You will need GNU make 4.0 or later to build the kernel.
110
111Bash
112----
113
114Some bash scripts are used for the kernel build.
115Bash 4.2 or newer is needed.
116
117Binutils
118--------
119
120Binutils 2.25 or newer is needed to build the kernel.
121
122pkg-config
123----------
124
125The build system, as of 4.18, requires pkg-config to check for installed
126kconfig tools and to determine flags settings for use in
127'make {g,x}config'. Previously pkg-config was being used but not
128verified or documented.
129
130Flex
131----
132
133Since Linux 4.16, the build system generates lexical analyzers
134during build. This requires flex 2.5.35 or later.
135
136
137Bison
138-----
139
140Since Linux 4.16, the build system generates parsers
141during build. This requires bison 2.0 or later.
142
143pahole
144------
145
146Since Linux 5.2, if CONFIG_DEBUG_INFO_BTF is selected, the build system
147generates BTF (BPF Type Format) from DWARF in vmlinux, a bit later from kernel
148modules as well. This requires pahole v1.16 or later.
149
150It is found in the 'dwarves' or 'pahole' distro packages or from
151https://fedorapeople.org/~acme/dwarves/.
152
153Perl
154----
155
156You will need perl 5 and the following modules: ``Getopt::Long``,
157``Getopt::Std``, ``File::Basename``, and ``File::Find`` to build the kernel.
158
159BC
160--
161
162You will need bc to build kernels 3.10 and higher
163
164
165OpenSSL
166-------
167
168Module signing and external certificate handling use the OpenSSL program and
169crypto library to do key creation and signature generation.
170
171You will need openssl to build kernels 3.7 and higher if module signing is
172enabled. You will also need openssl development packages to build kernels 4.3
173and higher.
174
175Tar
176---
177
178GNU tar is needed if you want to enable access to the kernel headers via sysfs
179(CONFIG_IKHEADERS).
180
181gtags / GNU GLOBAL (optional)
182-----------------------------
183
184The kernel build requires GNU GLOBAL version 6.6.5 or later to generate
185tag files through ``make gtags``. This is due to its use of the gtags
186``-C (--directory)`` flag.
187
188mkimage
189-------
190
191This tool is used when building a Flat Image Tree (FIT), commonly used on ARM
192platforms. The tool is available via the ``u-boot-tools`` package or can be
193built from the U-Boot source code. See the instructions at
194https://docs.u-boot.org/en/latest/build/tools.html#building-tools-for-linux
195
196GNU AWK
197-------
198
199GNU AWK is needed if you want kernel builds to generate address range data for
200builtin modules (CONFIG_BUILTIN_MODULE_RANGES).
201
202System utilities
203****************
204
205Architectural changes
206---------------------
207
208DevFS has been obsoleted in favour of udev
209(https://www.kernel.org/pub/linux/utils/kernel/hotplug/)
210
21132-bit UID support is now in place. Have fun!
212
213Linux documentation for functions is transitioning to inline
214documentation via specially-formatted comments near their
215definitions in the source. These comments can be combined with ReST
216files the Documentation/ directory to make enriched documentation, which can
217then be converted to PostScript, HTML, LaTex, ePUB and PDF files.
218In order to convert from ReST format to a format of your choice, you'll need
219Sphinx.
220
221Util-linux
222----------
223
224New versions of util-linux provide ``fdisk`` support for larger disks,
225support new options to mount, recognize more supported partition
226types, and similar goodies.
227You'll probably want to upgrade.
228
229Ksymoops
230--------
231
232If the unthinkable happens and your kernel oopses, you may need the
233ksymoops tool to decode it, but in most cases you don't.
234It is generally preferred to build the kernel with ``CONFIG_KALLSYMS`` so
235that it produces readable dumps that can be used as-is (this also
236produces better output than ksymoops). If for some reason your kernel
237is not build with ``CONFIG_KALLSYMS`` and you have no way to rebuild and
238reproduce the Oops with that option, then you can still decode that Oops
239with ksymoops.
240
241Mkinitrd
242--------
243
244These changes to the ``/lib/modules`` file tree layout also require that
245mkinitrd be upgraded.
246
247E2fsprogs
248---------
249
250The latest version of ``e2fsprogs`` fixes several bugs in fsck and
251debugfs. Obviously, it's a good idea to upgrade.
252
253JFSutils
254--------
255
256The ``jfsutils`` package contains the utilities for the file system.
257The following utilities are available:
258
259- ``fsck.jfs`` - initiate replay of the transaction log, and check
260 and repair a JFS formatted partition.
261
262- ``mkfs.jfs`` - create a JFS formatted partition.
263
264- other file system utilities are also available in this package.
265
266Reiserfsprogs
267-------------
268
269The reiserfsprogs package should be used for reiserfs-3.6.x
270(Linux kernels 2.4.x). It is a combined package and contains working
271versions of ``mkreiserfs``, ``resize_reiserfs``, ``debugreiserfs`` and
272``reiserfsck``. These utils work on both i386 and alpha platforms.
273
274Xfsprogs
275--------
276
277The latest version of ``xfsprogs`` contains ``mkfs.xfs``, ``xfs_db``, and the
278``xfs_repair`` utilities, among others, for the XFS filesystem. It is
279architecture independent and any version from 2.0.0 onward should
280work correctly with this version of the XFS kernel code (2.6.0 or
281later is recommended, due to some significant improvements).
282
283PCMCIAutils
284-----------
285
286PCMCIAutils replaces ``pcmcia-cs``. It properly sets up
287PCMCIA sockets at system startup and loads the appropriate modules
288for 16-bit PCMCIA devices if the kernel is modularized and the hotplug
289subsystem is used.
290
291Quota-tools
292-----------
293
294Support for 32 bit uid's and gid's is required if you want to use
295the newer version 2 quota format. Quota-tools version 3.07 and
296newer has this support. Use the recommended version or newer
297from the table above.
298
299Intel IA32 microcode
300--------------------
301
302A driver has been added to allow updating of Intel IA32 microcode,
303accessible as a normal (misc) character device. If you are not using
304udev you may need to::
305
306 mkdir /dev/cpu
307 mknod /dev/cpu/microcode c 10 184
308 chmod 0644 /dev/cpu/microcode
309
310as root before you can use this. You'll probably also want to
311get the user-space microcode_ctl utility to use with this.
312
313udev
314----
315
316``udev`` is a userspace application for populating ``/dev`` dynamically with
317only entries for devices actually present. ``udev`` replaces the basic
318functionality of devfs, while allowing persistent device naming for
319devices.
320
321FUSE
322----
323
324Needs libfuse 2.4.0 or later. Absolute minimum is 2.3.0 but mount
325options ``direct_io`` and ``kernel_cache`` won't work.
326
327Networking
328**********
329
330General changes
331---------------
332
333If you have advanced network configuration needs, you should probably
334consider using the network tools from ip-route2.
335
336Packet Filter / NAT
337-------------------
338The packet filtering and NAT code uses the same tools like the previous 2.4.x
339kernel series (iptables). It still includes backwards-compatibility modules
340for 2.2.x-style ipchains and 2.0.x-style ipfwadm.
341
342PPP
343---
344
345The PPP driver has been restructured to support multilink and to
346enable it to operate over diverse media layers. If you use PPP,
347upgrade pppd to at least 2.4.0.
348
349If you are not using udev, you must have the device file /dev/ppp
350which can be made by::
351
352 mknod /dev/ppp c 108 0
353
354as root.
355
356NFS-utils
357---------
358
359In ancient (2.4 and earlier) kernels, the nfs server needed to know
360about any client that expected to be able to access files via NFS. This
361information would be given to the kernel by ``mountd`` when the client
362mounted the filesystem, or by ``exportfs`` at system startup. exportfs
363would take information about active clients from ``/var/lib/nfs/rmtab``.
364
365This approach is quite fragile as it depends on rmtab being correct
366which is not always easy, particularly when trying to implement
367fail-over. Even when the system is working well, ``rmtab`` suffers from
368getting lots of old entries that never get removed.
369
370With modern kernels we have the option of having the kernel tell mountd
371when it gets a request from an unknown host, and mountd can give
372appropriate export information to the kernel. This removes the
373dependency on ``rmtab`` and means that the kernel only needs to know about
374currently active clients.
375
376To enable this new functionality, you need to::
377
378 mount -t nfsd nfsd /proc/fs/nfsd
379
380before running exportfs or mountd. It is recommended that all NFS
381services be protected from the internet-at-large by a firewall where
382that is possible.
383
384mcelog
385------
386
387On x86 kernels the mcelog utility is needed to process and log machine check
388events when ``CONFIG_X86_MCE`` is enabled. Machine check events are errors
389reported by the CPU. Processing them is strongly encouraged.
390
391Kernel documentation
392********************
393
394Sphinx
395------
396
397Please see :ref:`sphinx_install` in :ref:`Documentation/doc-guide/sphinx.rst <sphinxdoc>`
398for details about Sphinx requirements.
399
400rustdoc
401-------
402
403``rustdoc`` is used to generate the documentation for Rust code. Please see
404Documentation/rust/general-information.rst for more information.
405
406Getting updated software
407========================
408
409Kernel compilation
410******************
411
412gcc
413---
414
415- <ftp://ftp.gnu.org/gnu/gcc/>
416
417Clang/LLVM
418----------
419
420- :ref:`Getting LLVM <getting_llvm>`.
421
422Rust
423----
424
425- Documentation/rust/quick-start.rst.
426
427bindgen
428-------
429
430- Documentation/rust/quick-start.rst.
431
432Make
433----
434
435- <ftp://ftp.gnu.org/gnu/make/>
436
437Bash
438----
439
440- <ftp://ftp.gnu.org/gnu/bash/>
441
442Binutils
443--------
444
445- <https://www.kernel.org/pub/linux/devel/binutils/>
446
447Flex
448----
449
450- <https://github.com/westes/flex/releases>
451
452Bison
453-----
454
455- <ftp://ftp.gnu.org/gnu/bison/>
456
457OpenSSL
458-------
459
460- <https://www.openssl.org/>
461
462System utilities
463****************
464
465Util-linux
466----------
467
468- <https://www.kernel.org/pub/linux/utils/util-linux/>
469
470Kmod
471----
472
473- <https://www.kernel.org/pub/linux/utils/kernel/kmod/>
474- <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git>
475
476Ksymoops
477--------
478
479- <https://www.kernel.org/pub/linux/utils/kernel/ksymoops/v2.4/>
480
481Mkinitrd
482--------
483
484- <https://code.launchpad.net/initrd-tools/main>
485
486E2fsprogs
487---------
488
489- <https://www.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/>
490- <https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git/>
491
492JFSutils
493--------
494
495- <https://jfs.sourceforge.net/>
496
497Reiserfsprogs
498-------------
499
500- <https://git.kernel.org/pub/scm/linux/kernel/git/jeffm/reiserfsprogs.git/>
501
502Xfsprogs
503--------
504
505- <https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git>
506- <https://www.kernel.org/pub/linux/utils/fs/xfs/xfsprogs/>
507
508Pcmciautils
509-----------
510
511- <https://www.kernel.org/pub/linux/utils/kernel/pcmcia/>
512
513Quota-tools
514-----------
515
516- <https://sourceforge.net/projects/linuxquota/>
517
518
519Intel P6 microcode
520------------------
521
522- <https://downloadcenter.intel.com/>
523
524udev
525----
526
527- <https://www.freedesktop.org/software/systemd/man/udev.html>
528
529FUSE
530----
531
532- <https://github.com/libfuse/libfuse/releases>
533
534mcelog
535------
536
537- <https://www.mcelog.org/>
538
539cpio
540----
541
542- <https://www.gnu.org/software/cpio/>
543
544Networking
545**********
546
547PPP
548---
549
550- <https://download.samba.org/pub/ppp/>
551- <https://git.ozlabs.org/?p=ppp.git>
552- <https://github.com/paulusmack/ppp/>
553
554NFS-utils
555---------
556
557- <https://sourceforge.net/project/showfiles.php?group_id=14>
558- <https://nfs.sourceforge.net/>
559
560Iptables
561--------
562
563- <https://netfilter.org/projects/iptables/index.html>
564
565Ip-route2
566---------
567
568- <https://www.kernel.org/pub/linux/utils/net/iproute2/>
569
570OProfile
571--------
572
573- <https://oprofile.sf.net/download/>
574
575Kernel documentation
576********************
577
578Sphinx
579------
580
581- <https://www.sphinx-doc.org/>
1.. _changes:
2
3Minimal requirements to compile the Kernel
4++++++++++++++++++++++++++++++++++++++++++
5
6Intro
7=====
8
9This document is designed to provide a list of the minimum levels of
10software necessary to run the 4.x kernels.
11
12This document is originally based on my "Changes" file for 2.0.x kernels
13and therefore owes credit to the same people as that file (Jared Mauch,
14Axel Boldt, Alessandro Sigala, and countless other users all over the
15'net).
16
17Current Minimal Requirements
18****************************
19
20Upgrade to at **least** these software revisions before thinking you've
21encountered a bug! If you're unsure what version you're currently
22running, the suggested command should tell you.
23
24Again, keep in mind that this list assumes you are already functionally
25running a Linux kernel. Also, not all tools are necessary on all
26systems; obviously, if you don't have any PC Card hardware, for example,
27you probably needn't concern yourself with pcmciautils.
28
29====================== =============== ========================================
30 Program Minimal version Command to check the version
31====================== =============== ========================================
32GNU C 4.9 gcc --version
33Clang/LLVM (optional) 10.0.1 clang --version
34GNU make 3.81 make --version
35binutils 2.23 ld -v
36flex 2.5.35 flex --version
37bison 2.0 bison --version
38util-linux 2.10o fdformat --version
39kmod 13 depmod -V
40e2fsprogs 1.41.4 e2fsck -V
41jfsutils 1.1.3 fsck.jfs -V
42reiserfsprogs 3.6.3 reiserfsck -V
43xfsprogs 2.6.0 xfs_db -V
44squashfs-tools 4.0 mksquashfs -version
45btrfs-progs 0.18 btrfsck
46pcmciautils 004 pccardctl -V
47quota-tools 3.09 quota -V
48PPP 2.4.0 pppd --version
49nfs-utils 1.0.5 showmount --version
50procps 3.2.0 ps --version
51udev 081 udevd --version
52grub 0.93 grub --version || grub-install --version
53mcelog 0.6 mcelog --version
54iptables 1.4.2 iptables -V
55openssl & libcrypto 1.0.0 openssl version
56bc 1.06.95 bc --version
57Sphinx\ [#f1]_ 1.3 sphinx-build --version
58====================== =============== ========================================
59
60.. [#f1] Sphinx is needed only to build the Kernel documentation
61
62Kernel compilation
63******************
64
65GCC
66---
67
68The gcc version requirements may vary depending on the type of CPU in your
69computer.
70
71Clang/LLVM (optional)
72---------------------
73
74The latest formal release of clang and LLVM utils (according to
75`releases.llvm.org <https://releases.llvm.org>`_) are supported for building
76kernels. Older releases aren't guaranteed to work, and we may drop workarounds
77from the kernel that were used to support older versions. Please see additional
78docs on :ref:`Building Linux with Clang/LLVM <kbuild_llvm>`.
79
80Make
81----
82
83You will need GNU make 3.81 or later to build the kernel.
84
85Binutils
86--------
87
88Binutils 2.23 or newer is needed to build the kernel.
89
90pkg-config
91----------
92
93The build system, as of 4.18, requires pkg-config to check for installed
94kconfig tools and to determine flags settings for use in
95'make {g,x}config'. Previously pkg-config was being used but not
96verified or documented.
97
98Flex
99----
100
101Since Linux 4.16, the build system generates lexical analyzers
102during build. This requires flex 2.5.35 or later.
103
104
105Bison
106-----
107
108Since Linux 4.16, the build system generates parsers
109during build. This requires bison 2.0 or later.
110
111Perl
112----
113
114You will need perl 5 and the following modules: ``Getopt::Long``,
115``Getopt::Std``, ``File::Basename``, and ``File::Find`` to build the kernel.
116
117BC
118--
119
120You will need bc to build kernels 3.10 and higher
121
122
123OpenSSL
124-------
125
126Module signing and external certificate handling use the OpenSSL program and
127crypto library to do key creation and signature generation.
128
129You will need openssl to build kernels 3.7 and higher if module signing is
130enabled. You will also need openssl development packages to build kernels 4.3
131and higher.
132
133
134System utilities
135****************
136
137Architectural changes
138---------------------
139
140DevFS has been obsoleted in favour of udev
141(https://www.kernel.org/pub/linux/utils/kernel/hotplug/)
142
14332-bit UID support is now in place. Have fun!
144
145Linux documentation for functions is transitioning to inline
146documentation via specially-formatted comments near their
147definitions in the source. These comments can be combined with ReST
148files the Documentation/ directory to make enriched documentation, which can
149then be converted to PostScript, HTML, LaTex, ePUB and PDF files.
150In order to convert from ReST format to a format of your choice, you'll need
151Sphinx.
152
153Util-linux
154----------
155
156New versions of util-linux provide ``fdisk`` support for larger disks,
157support new options to mount, recognize more supported partition
158types, have a fdformat which works with 2.4 kernels, and similar goodies.
159You'll probably want to upgrade.
160
161Ksymoops
162--------
163
164If the unthinkable happens and your kernel oopses, you may need the
165ksymoops tool to decode it, but in most cases you don't.
166It is generally preferred to build the kernel with ``CONFIG_KALLSYMS`` so
167that it produces readable dumps that can be used as-is (this also
168produces better output than ksymoops). If for some reason your kernel
169is not build with ``CONFIG_KALLSYMS`` and you have no way to rebuild and
170reproduce the Oops with that option, then you can still decode that Oops
171with ksymoops.
172
173Mkinitrd
174--------
175
176These changes to the ``/lib/modules`` file tree layout also require that
177mkinitrd be upgraded.
178
179E2fsprogs
180---------
181
182The latest version of ``e2fsprogs`` fixes several bugs in fsck and
183debugfs. Obviously, it's a good idea to upgrade.
184
185JFSutils
186--------
187
188The ``jfsutils`` package contains the utilities for the file system.
189The following utilities are available:
190
191- ``fsck.jfs`` - initiate replay of the transaction log, and check
192 and repair a JFS formatted partition.
193
194- ``mkfs.jfs`` - create a JFS formatted partition.
195
196- other file system utilities are also available in this package.
197
198Reiserfsprogs
199-------------
200
201The reiserfsprogs package should be used for reiserfs-3.6.x
202(Linux kernels 2.4.x). It is a combined package and contains working
203versions of ``mkreiserfs``, ``resize_reiserfs``, ``debugreiserfs`` and
204``reiserfsck``. These utils work on both i386 and alpha platforms.
205
206Xfsprogs
207--------
208
209The latest version of ``xfsprogs`` contains ``mkfs.xfs``, ``xfs_db``, and the
210``xfs_repair`` utilities, among others, for the XFS filesystem. It is
211architecture independent and any version from 2.0.0 onward should
212work correctly with this version of the XFS kernel code (2.6.0 or
213later is recommended, due to some significant improvements).
214
215PCMCIAutils
216-----------
217
218PCMCIAutils replaces ``pcmcia-cs``. It properly sets up
219PCMCIA sockets at system startup and loads the appropriate modules
220for 16-bit PCMCIA devices if the kernel is modularized and the hotplug
221subsystem is used.
222
223Quota-tools
224-----------
225
226Support for 32 bit uid's and gid's is required if you want to use
227the newer version 2 quota format. Quota-tools version 3.07 and
228newer has this support. Use the recommended version or newer
229from the table above.
230
231Intel IA32 microcode
232--------------------
233
234A driver has been added to allow updating of Intel IA32 microcode,
235accessible as a normal (misc) character device. If you are not using
236udev you may need to::
237
238 mkdir /dev/cpu
239 mknod /dev/cpu/microcode c 10 184
240 chmod 0644 /dev/cpu/microcode
241
242as root before you can use this. You'll probably also want to
243get the user-space microcode_ctl utility to use with this.
244
245udev
246----
247
248``udev`` is a userspace application for populating ``/dev`` dynamically with
249only entries for devices actually present. ``udev`` replaces the basic
250functionality of devfs, while allowing persistent device naming for
251devices.
252
253FUSE
254----
255
256Needs libfuse 2.4.0 or later. Absolute minimum is 2.3.0 but mount
257options ``direct_io`` and ``kernel_cache`` won't work.
258
259Networking
260**********
261
262General changes
263---------------
264
265If you have advanced network configuration needs, you should probably
266consider using the network tools from ip-route2.
267
268Packet Filter / NAT
269-------------------
270The packet filtering and NAT code uses the same tools like the previous 2.4.x
271kernel series (iptables). It still includes backwards-compatibility modules
272for 2.2.x-style ipchains and 2.0.x-style ipfwadm.
273
274PPP
275---
276
277The PPP driver has been restructured to support multilink and to
278enable it to operate over diverse media layers. If you use PPP,
279upgrade pppd to at least 2.4.0.
280
281If you are not using udev, you must have the device file /dev/ppp
282which can be made by::
283
284 mknod /dev/ppp c 108 0
285
286as root.
287
288NFS-utils
289---------
290
291In ancient (2.4 and earlier) kernels, the nfs server needed to know
292about any client that expected to be able to access files via NFS. This
293information would be given to the kernel by ``mountd`` when the client
294mounted the filesystem, or by ``exportfs`` at system startup. exportfs
295would take information about active clients from ``/var/lib/nfs/rmtab``.
296
297This approach is quite fragile as it depends on rmtab being correct
298which is not always easy, particularly when trying to implement
299fail-over. Even when the system is working well, ``rmtab`` suffers from
300getting lots of old entries that never get removed.
301
302With modern kernels we have the option of having the kernel tell mountd
303when it gets a request from an unknown host, and mountd can give
304appropriate export information to the kernel. This removes the
305dependency on ``rmtab`` and means that the kernel only needs to know about
306currently active clients.
307
308To enable this new functionality, you need to::
309
310 mount -t nfsd nfsd /proc/fs/nfsd
311
312before running exportfs or mountd. It is recommended that all NFS
313services be protected from the internet-at-large by a firewall where
314that is possible.
315
316mcelog
317------
318
319On x86 kernels the mcelog utility is needed to process and log machine check
320events when ``CONFIG_X86_MCE`` is enabled. Machine check events are errors
321reported by the CPU. Processing them is strongly encouraged.
322
323Kernel documentation
324********************
325
326Sphinx
327------
328
329Please see :ref:`sphinx_install` in :ref:`Documentation/doc-guide/sphinx.rst <sphinxdoc>`
330for details about Sphinx requirements.
331
332Getting updated software
333========================
334
335Kernel compilation
336******************
337
338gcc
339---
340
341- <ftp://ftp.gnu.org/gnu/gcc/>
342
343Clang/LLVM
344----------
345
346- :ref:`Getting LLVM <getting_llvm>`.
347
348Make
349----
350
351- <ftp://ftp.gnu.org/gnu/make/>
352
353Binutils
354--------
355
356- <https://www.kernel.org/pub/linux/devel/binutils/>
357
358Flex
359----
360
361- <https://github.com/westes/flex/releases>
362
363Bison
364-----
365
366- <ftp://ftp.gnu.org/gnu/bison/>
367
368OpenSSL
369-------
370
371- <https://www.openssl.org/>
372
373System utilities
374****************
375
376Util-linux
377----------
378
379- <https://www.kernel.org/pub/linux/utils/util-linux/>
380
381Kmod
382----
383
384- <https://www.kernel.org/pub/linux/utils/kernel/kmod/>
385- <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git>
386
387Ksymoops
388--------
389
390- <https://www.kernel.org/pub/linux/utils/kernel/ksymoops/v2.4/>
391
392Mkinitrd
393--------
394
395- <https://code.launchpad.net/initrd-tools/main>
396
397E2fsprogs
398---------
399
400- <https://www.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/>
401- <https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git/>
402
403JFSutils
404--------
405
406- <http://jfs.sourceforge.net/>
407
408Reiserfsprogs
409-------------
410
411- <https://git.kernel.org/pub/scm/linux/kernel/git/jeffm/reiserfsprogs.git/>
412
413Xfsprogs
414--------
415
416- <https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git>
417- <https://www.kernel.org/pub/linux/utils/fs/xfs/xfsprogs/>
418
419Pcmciautils
420-----------
421
422- <https://www.kernel.org/pub/linux/utils/kernel/pcmcia/>
423
424Quota-tools
425-----------
426
427- <http://sourceforge.net/projects/linuxquota/>
428
429
430Intel P6 microcode
431------------------
432
433- <https://downloadcenter.intel.com/>
434
435udev
436----
437
438- <https://www.freedesktop.org/software/systemd/man/udev.html>
439
440FUSE
441----
442
443- <https://github.com/libfuse/libfuse/releases>
444
445mcelog
446------
447
448- <http://www.mcelog.org/>
449
450Networking
451**********
452
453PPP
454---
455
456- <https://download.samba.org/pub/ppp/>
457- <https://git.ozlabs.org/?p=ppp.git>
458- <https://github.com/paulusmack/ppp/>
459
460NFS-utils
461---------
462
463- <http://sourceforge.net/project/showfiles.php?group_id=14>
464
465Iptables
466--------
467
468- <https://netfilter.org/projects/iptables/index.html>
469
470Ip-route2
471---------
472
473- <https://www.kernel.org/pub/linux/utils/net/iproute2/>
474
475OProfile
476--------
477
478- <http://oprofile.sf.net/download/>
479
480NFS-Utils
481---------
482
483- <http://nfs.sourceforge.net/>
484
485Kernel documentation
486********************
487
488Sphinx
489------
490
491- <https://www.sphinx-doc.org/>