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<translate>{{Announce|To help us translate this documentation, {{CreateAccount}}, log in to the wiki. Then go to Actions -> Translate in the menu, or click the "Translate this page" link, above. You will be able to select small parts of the install docs and translate these parts to your native language.}}
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{{Announce|To help us translate this documentation, {{CreateAccount}}, log in to the wiki. Then go to Actions -> Translate in the menu, or click the "Translate this page" link, above. You will be able to select small parts of the install docs and translate these parts to your native language.}}


<!--T:2-->
This Section will give you an overview of kernels used in funtoo.
This Section will give you an overview of kernels used in funtoo.
Some points of interest:
Some points of interest:


<!--T:3-->
* Most Funtoo Linux kernels support the handy {{c|[[#Binary USE|binary]]}} USE flag, described below.
* Most Funtoo Linux kernels support the handy {{c|[[#Binary USE|binary]]}} USE flag, described below.
* Funtoo Linux offers quality kernels from other Linux Distributions, like {{c|debian-sources}}.
* Funtoo Linux offers quality kernels from other Linux Distributions, like {{c|debian-sources}}.
* Advanced users may want to take a look at [[Additional Kernel Resources]].
* Advanced users may want to take a look at [[Additional Kernel Resources]].


== Overview of Kernels ==
== Overview of Kernels == <!--T:4-->


=== {{Package|sys-kernel/debian-sources-lts}} ===
=== {{Package|sys-kernel/debian-sources-lts}} === <!--T:5-->


This is the Debian kernel, long-term stable edition and the default kernel for Funtoo Linux. '''These ebuilds now support the {{c|binary}} USE flag.''' Daniel has added a special {{c|config-extract}} command which can be used to list all available official Debian kernel configurations, and generate them from the Debian files included with the kernel.
<!--T:6-->
This is the Debian kernel, long-term stable edition and the default kernel for Funtoo Linux. '''These ebuilds now support the {{c|binary}} USE flag.'''


=== {{Package|sys-kernel/debian-sources}} ===
=== {{Package|sys-kernel/debian-sources}} === <!--T:7-->


<!--T:8-->
This is a more up-to-date version of the Debian kernel but it less suited for server systems.
This is a more up-to-date version of the Debian kernel but it less suited for server systems.


== Binary USE ==
== Binary USE == <!--T:9-->


<!--T:10-->
Many of the kernel ebuilds in Funtoo Linux support the very useful {{c|binary}} USE flag. By enabling this USE flag and emerging the kernel, the ebuild will automatically build a binary kernel image, initramfs and kernel modules and install them to {{c|/boot}}. The binary kernel image and initramfs can be used to boot your Funtoo Linux system without requiring any additional configuration. This is a great way to get a Funtoo Linux system up and running quickly. Here's how to do it:
Many of the kernel ebuilds in Funtoo Linux support the very useful {{c|binary}} USE flag. By enabling this USE flag and emerging the kernel, the ebuild will automatically build a binary kernel image, initramfs and kernel modules and install them to {{c|/boot}}. The binary kernel image and initramfs can be used to boot your Funtoo Linux system without requiring any additional configuration. This is a great way to get a Funtoo Linux system up and running quickly. Here's how to do it:


<!--T:11-->
{{console|body=
{{console|body=
###i## echo "sys-kernel/debian-sources binary" >> /etc/portage/package.use
###i## echo "sys-kernel/debian-sources binary" >> /etc/portage/package.use
Line 31: Line 38:
}}
}}


<!--T:12-->
Once you have a functional kernel, and want to slim things down a bit, it may be worth your time to investigate the make targets
known as localmodconfig and localyesconfig to create a kernel config based on current running hardware..
<!--T:13-->
More information can be found in the [[Funtoo Linux Installation]] Guide.
More information can be found in the [[Funtoo Linux Installation]] Guide.


== Funtoo Linux Genkernel ==
<!--T:14-->
 
Funtoo Linux contains a forked/enhanced version of genkernel with the following new capabilities:
 
* genkernel can use a build directory that is separate from the kernel source directory. This is enabled using the new {{c|--build-dst}} option.
* {{c|--build-src}} is a new option that is equivalent to the {{c|--kerneldir}} option.
* {{c|--fullname}} can be used to specify the entire name of the kernel and initramfs images -- everything after {{c|kernel-}} and {{c|initramfs-}}.
* {{c|--firmware-src}} - a new option that works identically to {{c|--firmware-dir}}.
* {{c|--firmware-dst}} - a new capability - you can now define where genkernel installs firmware.
* Genkernel uses Funtoo Linux {{c|lvm2}} rather than building its own.
* Some compile fixes.
 
== Using Debian-Sources with Genkernel ==
 
{{fancyimportant|Debian-sources is now fully compatible with the ''binary'' USE flag and recommended for desktop users. The below example is valid for manual installation. At least 19G of disc space required to build. Take this into account, when using separate /var or using virtual machines with limited size}}
 
This section describes how to build a binary kernel with ''{{c|debian-sources}}'' and ''{{c|genkernel}}'', and it also explains how to use Funtoo Linux's ''{{c|config-extract}}'' tool to list and create official Debian kernel configurations.
 
=== First step: emerging the required packages ===
 
The first step is to emerge:
 
# The Debian sources
# Genkernel itself
 
This is achieved by running the following:
 
<console>
###i## emerge -av sys-kernel/debian-sources sys-kernel/genkernel
</console>
 
Once the Debian kernel sources are deployed, you should find a directory named '''linux-debian-''version''''' (e.g. linux-debian-2.6.32.30) under '''{{c|/usr/src}}'''. Update your the '''{{c|linux}}''' symlink to point on this directory:
<console>
###i## cd /usr/src
###i## rm linux
###i## ln -s linux-debian-2.6.32.30 linux
</console>
 
Alternatively, emerge the debian-sources with the ''{{c|symlink}}'' USE flag.
 
=== Second step: Grabbing a configuration file ===
 
If is now time to download the kernel configuration file. For this tutorial we will use a configuration file for AMD64 (several others architectures like MIPS or SPARC64 are available.)  To view a complete list of available kernel configurations, type {{c|./config-extract -l}} '''in the Debian kernel source directory''':
 
<pre>
ninja1 linux-debian-2.6.32.30 # ./config-extract -l
 
====== standard featureset ======
 
      alpha: alpha-generic, alpha-legacy, alpha-smp
      amd64
      armel: iop32x, ixp4xx, kirkwood, orion5x, versatile
        hppa: parisc, parisc-smp, parisc64, parisc64-smp
        i386: 486, 686, 686-bigmem, amd64
        ia64: itanium, mckinley
        m68k: amiga, atari, bvme6000, mac, mvme147, mvme16x
        mips: 4kc-malta, 5kc-malta, r4k-ip22, r5k-ip32, sb1-bcm91250a, sb1a-bcm91480b
      mipsel: 4kc-malta, 5kc-malta, r5k-cobalt, sb1-bcm91250a, sb1a-bcm91480b
    powerpc: powerpc, powerpc-smp, powerpc64
        s390: s390x, s390x-tape
        sh4: sh7751r, sh7785lcr
      sparc: sparc64, sparc64-smp
    sparc64: sparc64, sparc64-smp
 
====== vserver featureset ======
 
      amd64
        i386: 686, 686-bigmem
        ia64: itanium, mckinley
    powerpc: powerpc, powerpc64
        s390
      sparc
    sparc64
 
====== xen featureset ======
 
      amd64
        i386
 
====== openvz featureset ======
 
      amd64
        i386
</pre>
 
Type {{c|config-extract -h}} for extended usage information:
 
<pre>
ninja1 linux-debian-2.6.32.30 # ./config-extract -h
This work is free software.
 
Copyright 2011 Funtoo Technologies. You can redistribute and/or modify it under
the terms of the GNU General Public License version 3 as published by the Free
Software Foundation. Alternatively you may (at your option) use any other
license that has been publicly approved for use with this program by Funtoo
Technologies (or its successors, if any.)
 
usage: config-extract [options] arch [featureset] [subarch]
 
  -h  --help        print this usage and exit
  -l  --list        list all available kernel configurations
  -o  --outfile    specify kernel config outfile --
                    defaults to .config in current directory
  [featureset]      defaults to "none" if not specified
  [subarch]        defaults to the only one available; otherwise required
 
This program was written by Daniel Robbins for Funtoo Linux, for the purpose of
easily and conveniently extracting Debian kernel configurations. To see a nice
list of all available kernel configurations, use the --list option.
 
Debian's kernel configs are specified internally in arch_featureset_flavor
format, such as: "amd64_openvz_amd64". The featureset typically describes an
optional kernel configuration such as "xen" or "openvz", while the flavor in
Debian terminology typically refers to the sub-architecture of the CPU.
 
When using this command, you must specify an arch. A featureset of "none" is
assumed unless you specify one, and by default this program will pick the only
available subarch if there is only one to choose from. If not, you will need to
pick one (and the program will remind you to do this.)
 
The kernel configuration will be written to ".config" in the current directory,
or the location you specified using the -o/--outfile option.
</pre>
 
Let's use {{c|config-extract}} to create a kernel configuration for an amd64 system:
 
<console>
# ##i##cd linux
# ##i##./config-extract amd64 standard amd64
Wrote amd64_none_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.
</console>
 
{{c|config-extract}} also allows you to extract special Debian featuresets, such as settings for Xen and [[OpenVZ]] kernels:
 
<console>
# ##i##./config-extract amd64 openvz
Wrote amd64_openvz_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.
</console>
 
'''It is necessary to name the kernel configuration file something other than ".config" to avoid errors with genkernel.'''
 
 
After using {{c|config-extract}}, run {{c|make oldconfig}} and accept all default options by hitting Enter at all prompts.
 
{{fancynote|if you are using the XFS file system as your root partition: Run {{c|make menuconfig}} and ensure that "File Systems --> XFS filesystem support" and "Library Routines --> CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" are both set to * (and not [m]).}}
This is needed to ensure that your system can boot up correctly for kernel versions >= 3.10.11.
 
=== Third step: Building and installing the kernel ===
 
This is simply achieved by:
 
<console>
# ##i##genkernel --kernel-config=config-2.6.32-5-amd64 all
</console>
 
* --kernel-config: use the given configfile. If you only give a filename here, it is searched for in your current working dir. You can also use a relative or an absolute path leading to your configfile here (for example: "--kernel-config=/usr/src/linux/configfile").
* all: rebuild the kernel image and the initramfs ramdisk image (aside of kernel modules, the ramdisk image contains tools such as BusyBox and some generic startup scripts, depending on options you use on the command line several additional tools like lvm or raid volume management can be incorporated as well).
 
{{ fancyimportant|Unless explicitly stated via ''--no-clean'' or ''--no-mrproper'', Genkernel will do a '''make mrproper''' in the kernel source tree, thus cleaning a previous build '''and removing the previous kernel configuration file''' in it.
}}
 
If you use Genkernel to rebuild a Linux kernel on SPARC64, remember to either:
* Set '''sparc64-unknown-linux-gnu-''' in ''General setup --> Cross-compiler tool prefix''
* Put '''--kernel-cross-compile=sparc64-unknown-linux-gnu-''' on the Genkernel command line
 
Once the kernel has been compiled and the ram disk has been generated, the kernel image plus its companion files (initramfs image and System.map) are placed in the /boot directory. You can use your favourite tool to update your bootloader configuration files.
 
[[Category:Internals]]
[[Category:Funtoo features]]
[[Category:Funtoo features]]
[[Category:Kernel]]
[[Category:Kernel]]

Latest revision as of 02:05, March 8, 2020

Other languages:
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   {{{title}}}
{{{body}}}

This Section will give you an overview of kernels used in funtoo. Some points of interest:

  • Most Funtoo Linux kernels support the handy binary USE flag, described below.
  • Funtoo Linux offers quality kernels from other Linux Distributions, like debian-sources.
  • Advanced users may want to take a look at Additional Kernel Resources.

Overview of Kernels

No results

This is the Debian kernel, long-term stable edition and the default kernel for Funtoo Linux. These ebuilds now support the binary USE flag.

sys-kernel/debian-sources

This is a more up-to-date version of the Debian kernel but it less suited for server systems.

Binary USE

Many of the kernel ebuilds in Funtoo Linux support the very useful binary USE flag. By enabling this USE flag and emerging the kernel, the ebuild will automatically build a binary kernel image, initramfs and kernel modules and install them to /boot. The binary kernel image and initramfs can be used to boot your Funtoo Linux system without requiring any additional configuration. This is a great way to get a Funtoo Linux system up and running quickly. Here's how to do it: 

root # echo "sys-kernel/debian-sources binary" >> /etc/portage/package.use
root # emerge debian-sources
root # nano -w /etc/boot.conf
root # ego boot update

Once you have a functional kernel, and want to slim things down a bit, it may be worth your time to investigate the make targets known as localmodconfig and localyesconfig to create a kernel config based on current running hardware..

More information can be found in the Funtoo Linux Installation Guide.

Retrieved from "https://www.funtoo.org/index.php?title=Funtoo_Linux_Kernels&oldid=31561"