Funtoo Linux Kernels/pt-br

From Funtoo
Revision as of 17:44, April 11, 2015 by Tocadotux (talk | contribs) (Kernel Features and Stability Overview)
Jump to: navigation, search

Overview of Kernels

sys-kernel/vanilla-sources

Isso vai instalar os fontes do kernel Linux "vanilla" (não modificado). A versão atual recomendada é a 3.x. Funtoo Linux que tem suporte totalmente ao Linux 3.x. As vantagens desse kernel incluem melhoramentos recentes ao Linux Containers, uma pilha de rede atual (networking stack) com muitas correções de bug, e alta confiabilidade para desktops e servidores. O lado negativo é que esse kernel deve ser configurado manualmente pelo usuário e não possui built-in genkernel suporte via a flag USE binary desta vez.

sys-kernel/gentoo-sources

Esse kernel tree é baseado nos kernels stable do kernel.org com genpatches aplicados genpatches. o Gentoo patchset visa ter suporte à toda variedade de arquiteturas suportadas pelo Gentoo. A lista de genpatched kernels disponíveis: genpatches-kernels

sys-kernel/openvz-rhel6-stable

Esse é um kernel baseado no RHEL6 com suporte a OpenVZ. Esse é agora o kernel preferido para desenvolvimento de produção OpenVZ (production OpenVZ deployments). Ele requer gcc-4.4.5 para ser construído, que vai usará automaticamente sem que o usuário precise utilizar gcc-config. Utilizamos essa versão de gcc desde que essa é a versão de gcc utilizada pela Red Hat para construir esse kernel.

sys-kernel/debian-sources

Esse é o kernel do Debian. Esses ebuilds agora possuem suporte a flag USE binary. Daniel adicionou comando especial config-extract que pode ser utilizado para listar todas as configurações disponíveis do kernel oficial do Debian, e gerá-las a partir dos arquivos do Debian inclusos com o kernel. Esse kernel tem suporte opcional a OpenVZ, mas é bem melhor utilizar o openvz-rhel6-stable se quiser um instalação OpenVZ com qualidade de produção (production-quality OpenVZ). Para mais informações sobre como utilizar debian-sources e config-extract, veja Utilizando debian-sources com o Genkernel abaixo.

Binary USE

Muitos dos kernel ebuilds no Funtoo Linux possuem suporte à flag USE binary muito útil. Ao habilitar essa flag USE e emergir o kernel, o ebuild construirá automaticamente uma imagem binária do kernel, o initramfs e módulos do kernel e instalá-los em /boot. A imagem binária do kernel e do initramfs pode ser utilizadas para inicializar seu sistema Funtoo Linux sem necessidade qualquer configuração adicional. Esse é um ótimo jeito de obter um sistema Funtoo Linux no ar e em execução rapidamente. Aqui está como fazer isso:

root # echo "sys-kernel/openvz-rhel6-stable binary" >> /etc/portage/package.use
root # emerge openvz-rhel6-stable
root # nano -w /etc/boot.conf
root # boot-update

Mais informações podem ser encontradas no Guia de Instalação do Funtoo Linux.

Funtoo Linux Genkernel

O Funtoo Linux contem uma versão forked/enhanced do genkernel com as novas compatibilidades:

  • genkernel pode utilizar um diretório build que é separado do diretório kernel source. Isso é habilitado utilizando a nova opção --build-dst.
  • --build-src é uma nova opção que é equivalente a opção --kerneldir.
  • --fullname pode ser utilizado para especificar o nome inteiro das imagens do kernel e do initramfs -- Tudo depois kernel- e de initramfs-.
  • --firmware-src - uma nova opção que funciona identic ao --firmware-dir.
  • --firmware-dst - uma nova compatibilidade - você pode agora definir onde o genkernel instala o firmware.
  • Genkernel utiliza o Funtoo Linux lvm2 ao invés de construir o seu próprio.
  • Algumas correções de compilação.

Estabilidade do Kernel e visão geral da estabilidade

   Warning

SPARC64: Todos os kernels além das séries 3.9 e antes do 3.14-rc8 estão sujeitos a um bug que abriga o kernel nas máquinas sun4v somente. Esses últimos são fornecidos com UltraSPARC T1 e mais recentes CPUs (ex. SunFire T1000, SunFire T2000, SunFire T52x0/T54x0 series...), todas as máquinas sun4u (UltraSPARC IV e CPUs antecedentes) não estão sujeitos a esse problema e qualquer versão de kernel funcional.

Nome do Kernel Versão USE flags Estabilidade Recursos Extras Req'd udev Notas
sys-kernel/vanilla-sources 3.17.0 N/A Excellent - recommended for desktops and servers. N/A Any Recommended for modern networking stack, hardware and Linux Containers support. This kernel must be manually configured by the user. New Features: kernelnewbies.org/linux_3.12 New Drivers: kernelnewbies/Linux_3.12-DriversArch
sys-kernel/gentoo-sources 3.17.0 N/A Excellent - recommended for desktops and workstations N/A Any Recommended for modern networking stack, hardware and Linux Containers support. This kernel must be manually configured by the user. New Features: kernelnewbies.org/linux_3.12 New Drivers: kernelnewbies/Linux_3.12-DriversArch
sys-kernel/openvz-rhel6-stable 2.6.32.042.092.2 binary Excellent - recommended for production servers N/A Any This kernel is built with gcc-4.4.5. emerge broadcom-netxtreme2 for reliable BCM5709+ support (integrated NIC)
sys-kernel/debian-sources 3.16.2, 3.16.7, 3.19.3 openvz Good - default kernel recommended by Funtoo OpenVZ (optional) Any See #Using debian-sources with Genkernel, below.

Using Debian-Sources with Genkernel

   Important

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 12G of /var/tmp required to build

This section describes how to build a binary kernel with debian-sources and genkernel, and it also explains how to use Funtoo Linux's config-extract tool to list and create official Debian kernel configurations.

First step: emerging the required packages

The first step is to emerge:

  1. The Debian sources
  2. Genkernel itself

This is achieved by running the following:

root # emerge -av sys-kernel/debian-sources sys-kernel/genkernel

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 /usr/src. Update your the linux symlink to point on this directory:

root # cd /usr/src
root # rm linux
root # ln -s linux-debian-2.6.32.30 linux

Alternatively, emerge the debian-sources with the 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 ./config-extract -l in the Debian kernel source directory:

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

Type config-extract -h for extended usage information:

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.

Let's use config-extract to create a kernel configuration for an amd64 system:

root # cd linux
root # ./config-extract amd64
Wrote amd64_none_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.

config-extract also allows you to extract special Debian featuresets, such as settings for Xen and OpenVZ kernels:

root # ./config-extract amd64 openvz
Wrote amd64_openvz_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.

It is necessary to name the kernel configuration file something other than ".config" to avoid errors with genkernel.


After using config-extract, run make oldconfig and accept all default options by hitting Enter at all prompts.


   Note

if you are using the XFS file system as your root partition: Run 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:

root # genkernel --kernel-config=config-2.6.32-5-amd64 all
  • --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).
   Important

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.