GCC¶

The gcc version requirements may vary depending on the type of CPU in yourcomputer.

Clang/LLVM (optional)¶

The latest formal release of clang and LLVM utils (according toreleases.llvm.org) are supported for buildingkernels. Older releases aren’t guaranteed to work, and we may drop workaroundsfrom the kernel that were used to support older versions. Please see additionaldocs onBuilding Linux with Clang/LLVM.

Rust (optional)¶

A recent version of the Rust compiler is required.

Please seeQuick Start for instructions on how tosatisfy the build requirements of Rust support. In particular, theMakefiletargetrustavailable is useful to check why the Rust toolchain may notbe detected.

bindgen (optional)¶

bindgen is used to generate the Rust bindings to the C side of the kernel.It depends onlibclang.

Make¶

You will need GNU make 4.0 or later to build the kernel.

Bash¶

Some bash scripts are used for the kernel build.Bash 4.2 or newer is needed.

Binutils¶

Binutils 2.30 or newer is needed to build the kernel.

pkg-config¶

The build system, as of 4.18, requires pkg-config to check for installedkconfig tools and to determine flags settings for use in‘make {g,x}config’. Previously pkg-config was being used but notverified or documented.

Flex¶

Since Linux 4.16, the build system generates lexical analyzersduring build. This requires flex 2.5.35 or later.

Bison¶

Since Linux 4.16, the build system generates parsersduring build. This requires bison 2.0 or later.

pahole¶

Since Linux 5.2, if CONFIG_DEBUG_INFO_BTF is selected, the build systemgenerates BTF (BPF Type Format) from DWARF in vmlinux, a bit later from kernelmodules as well. This requires pahole v1.16 or later.

It is found in the ‘dwarves’ or ‘pahole’ distro packages or fromhttps://fedorapeople.org/~acme/dwarves/.

Perl¶

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

Python¶

Several config options require it: it is required for arm/arm64default configs, CONFIG_LTO_CLANG, some DRM optional configs,the kernel-doc tool, and docs build (Sphinx), among others.

BC¶

You will need bc to build kernels 3.10 and higher

OpenSSL¶

Module signing and external certificate handling use the OpenSSL program andcrypto library to do key creation and signature generation.

You will need openssl to build kernels 3.7 and higher if module signing isenabled. You will also need openssl development packages to build kernels 4.3and higher.

Tar¶

GNU tar is needed if you want to enable access to the kernel headers via sysfs(CONFIG_IKHEADERS).

gtags / GNU GLOBAL (optional)¶

The kernel build requires GNU GLOBAL version 6.6.5 or later to generatetag files throughmakegtags. This is due to its use of the gtags-C(--directory) flag.

mkimage¶

This tool is used when building a Flat Image Tree (FIT), commonly used on ARMplatforms. The tool is available via theu-boot-tools package or can bebuilt from the U-Boot source code. See the instructions athttps://docs.u-boot.org/en/latest/build/tools.html#building-tools-for-linux

GNU AWK¶

GNU AWK is needed if you want kernel builds to generate address range data forbuiltin modules (CONFIG_BUILTIN_MODULE_RANGES).

Architectural changes¶

DevFS has been obsoleted in favour of udev(https://www.kernel.org/pub/linux/utils/kernel/hotplug/)

32-bit UID support is now in place. Have fun!

Linux documentation for functions is transitioning to inlinedocumentation via specially-formatted comments near theirdefinitions in the source. These comments can be combined with ReSTfiles the Documentation/ directory to make enriched documentation, which canthen be converted to PostScript, HTML, LaTex, ePUB and PDF files.In order to convert from ReST format to a format of your choice, you’ll needSphinx.

Util-linux¶

New versions of util-linux providefdisk support for larger disks,support new options to mount, recognize more supported partitiontypes, and similar goodies.You’ll probably want to upgrade.

Ksymoops¶

If the unthinkable happens and your kernel oopses, you may need theksymoops tool to decode it, but in most cases you don’t.It is generally preferred to build the kernel withCONFIG_KALLSYMS sothat it produces readable dumps that can be used as-is (this alsoproduces better output than ksymoops). If for some reason your kernelis not build withCONFIG_KALLSYMS and you have no way to rebuild andreproduce the Oops with that option, then you can still decode that Oopswith ksymoops.

Mkinitrd¶

These changes to the/lib/modules file tree layout also require thatmkinitrd be upgraded.

E2fsprogs¶

The latest version ofe2fsprogs fixes several bugs in fsck anddebugfs. Obviously, it’s a good idea to upgrade.

JFSutils¶

Thejfsutils package contains the utilities for the file system.The following utilities are available:

• fsck.jfs - initiate replay of the transaction log, and checkand repair a JFS formatted partition.

• mkfs.jfs - create a JFS formatted partition.

• other file system utilities are also available in this package.

Xfsprogs¶

The latest version ofxfsprogs containsmkfs.xfs,xfs_db, and thexfs_repair utilities, among others, for the XFS filesystem. It isarchitecture independent and any version from 2.0.0 onward shouldwork correctly with this version of the XFS kernel code (2.6.0 orlater is recommended, due to some significant improvements).

PCMCIAutils¶

PCMCIAutils replacespcmcia-cs. It properly sets upPCMCIA sockets at system startup and loads the appropriate modulesfor 16-bit PCMCIA devices if the kernel is modularized and the hotplugsubsystem is used.

Quota-tools¶

Support for 32 bit uid’s and gid’s is required if you want to usethe newer version 2 quota format. Quota-tools version 3.07 andnewer has this support. Use the recommended version or newerfrom the table above.

Intel IA32 microcode¶

A driver has been added to allow updating of Intel IA32 microcode,accessible as a normal (misc) character device. If you are not usingudev you may need to:

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

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

udev¶

udev is a userspace application for populating/dev dynamically withonly entries for devices actually present.udev replaces the basicfunctionality of devfs, while allowing persistent device naming fordevices.

FUSE¶

Needs libfuse 2.4.0 or later. Absolute minimum is 2.3.0 but mountoptionsdirect_io andkernel_cache won’t work.

General changes¶

If you have advanced network configuration needs, you should probablyconsider using the network tools from ip-route2.

Packet Filter / NAT¶

The packet filtering and NAT code uses the same tools like the previous 2.4.xkernel series (iptables). It still includes backwards-compatibility modulesfor 2.2.x-style ipchains and 2.0.x-style ipfwadm.

PPP¶

The PPP driver has been restructured to support multilink and toenable it to operate over diverse media layers. If you use PPP,upgrade pppd to at least 2.4.0.

If you are not using udev, you must have the device file /dev/pppwhich can be made by:

mknod /dev/ppp c 108 0

as root.

NFS-utils¶

In ancient (2.4 and earlier) kernels, the nfs server needed to knowabout any client that expected to be able to access files via NFS. Thisinformation would be given to the kernel bymountd when the clientmounted the filesystem, or byexportfs at system startup. exportfswould take information about active clients from/var/lib/nfs/rmtab.

This approach is quite fragile as it depends on rmtab being correctwhich is not always easy, particularly when trying to implementfail-over. Even when the system is working well,rmtab suffers fromgetting lots of old entries that never get removed.

With modern kernels we have the option of having the kernel tell mountdwhen it gets a request from an unknown host, and mountd can giveappropriate export information to the kernel. This removes thedependency onrmtab and means that the kernel only needs to know aboutcurrently active clients.

To enable this new functionality, you need to:

mount -t nfsd nfsd /proc/fs/nfsd

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

mcelog¶

On x86 kernels the mcelog utility is needed to process and log machine checkevents whenCONFIG_X86_MCE is enabled. Machine check events are errorsreported by the CPU. Processing them is strongly encouraged.

Sphinx¶

Please seeSphinx Install inDocumentation/doc-guide/sphinx.rstfor details about Sphinx requirements.

rustdoc¶

rustdoc is used to generate the documentation for Rust code. Please seeGeneral Information for more information.

gcc¶

• <ftp://ftp.gnu.org/gnu/gcc/>

Clang/LLVM¶

• Getting LLVM.

Rust¶

• Quick Start.

bindgen¶

• Quick Start.

Make¶

• <ftp://ftp.gnu.org/gnu/make/>

Bash¶

• <ftp://ftp.gnu.org/gnu/bash/>

Binutils¶

• <https://www.kernel.org/pub/linux/devel/binutils/>

Flex¶

• <https://github.com/westes/flex/releases>

Bison¶

• <ftp://ftp.gnu.org/gnu/bison/>

OpenSSL¶

• <https://www.openssl.org/>

Util-linux¶

• <https://www.kernel.org/pub/linux/utils/util-linux/>

Kmod¶

• <https://www.kernel.org/pub/linux/utils/kernel/kmod/>

• <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git>

Ksymoops¶

• <https://www.kernel.org/pub/linux/utils/kernel/ksymoops/v2.4/>

Mkinitrd¶

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

E2fsprogs¶

• <https://www.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/>

• <https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git/>

JFSutils¶

• <https://jfs.sourceforge.net/>

Xfsprogs¶

• <https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git>

• <https://www.kernel.org/pub/linux/utils/fs/xfs/xfsprogs/>

Pcmciautils¶

• <https://www.kernel.org/pub/linux/utils/kernel/pcmcia/>

Quota-tools¶

• <https://sourceforge.net/projects/linuxquota/>

Intel P6 microcode¶

• <https://downloadcenter.intel.com/>

udev¶

• <https://www.freedesktop.org/software/systemd/man/udev.html>

FUSE¶

• <https://github.com/libfuse/libfuse/releases>

mcelog¶

• <https://www.mcelog.org/>

PPP¶

• <https://download.samba.org/pub/ppp/>

• <https://git.ozlabs.org/?p=ppp.git>

• <https://github.com/paulusmack/ppp/>

NFS-utils¶

• <https://sourceforge.net/project/showfiles.php?group_id=14>

• <https://nfs.sourceforge.net/>

Iptables¶

• <https://netfilter.org/projects/iptables/index.html>

Ip-route2¶

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

OProfile¶

• <https://oprofile.sf.net/download/>

Sphinx¶

• <https://www.sphinx-doc.org/>