Commit 0d8aa321 authored by Thorsten Leemhuis's avatar Thorsten Leemhuis Committed by Jonathan Corbet
Browse files

docs: quickly-build-trimmed-linux: various small fixes and improvements 



* improve the short description of localmodconfig in the step-by-step
  guide while fixing its broken first sentence

* briefly mention immutable Linux distributions

* use '--shallow-exclude=v6.0' throughout the document

* instead of "git reset --hard; git checkout ..." use "git checkout
  --force ..." in the step-by-step guide: this matches the TLDR and is
  one command less to execute. This led to a few small adjustments to
  the text and the flow in the surrounding area.

* fix two thinkos in the section explaining full git clones

Signed-off-by: default avatarThorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/r/6f4684b9a5d11d3adb04e0af3cfc60db8b28eeb2.1684140700.git.linux@leemhuis.info


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent 96e3cc27

Documentation/admin-guide/quickly-build-trimmed-linux.rst

+27 −22
Original line number Diff line number Diff line
@@ -215,12 +215,14 @@ again. 
   reduce the compile time enormously, especially if you are running an

   universal kernel from a commodity Linux distribution.



   There is a catch: the make target 'localmodconfig' will disable kernel

   features you have not directly or indirectly through some program utilized

   since you booted the system. You can reduce or nearly eliminate that risk by

   using tricks outlined in the reference section; for quick testing purposes

   that risk is often negligible, but it is an aspect you want to keep in mind

   in case your kernel behaves oddly.

   There is a catch: 'localmodconfig' is likely to disable kernel features you

   did not use since you booted your Linux -- like drivers for currently

   disconnected peripherals or a virtualization software not haven't used yet.

   You can reduce or nearly eliminate that risk with tricks the reference

   section outlines; but when building a kernel just for quick testing purposes

   it is often negligible if such features are missing. But you should keep that

   aspect in mind when using a kernel built with this make target, as it might

   be the reason why something you only use occasionally stopped working.



   [:ref:`details<configuration>`]
@@ -271,6 +273,9 @@ again. 
   does nothing at all; in that case you have to manually install your kernel,

   as outlined in the reference section.



   If you are running a immutable Linux distribution, check its documentation

   and the web to find out how to install your own kernel there.



   [:ref:`details<install>`]



.. _another_sbs:
@@ -291,29 +296,29 @@ again. 
   version you care about, as git otherwise might retrieve the entire commit

   history::



     git fetch --shallow-exclude=v6.1 origin



   If you modified the sources (for example by applying a patch), you now need

   to discard those modifications; that's because git otherwise will not be able

   to switch to the sources of another version due to potential conflicting

   changes::



     git reset --hard

     git fetch --shallow-exclude=v6.0 origin



   Now checkout the version you are interested in, as explained above::

   Now switch to the version you are interested in -- but be aware the command

   used here will discard any modifications you performed, as they would

   conflict with the sources you want to checkout::



     git checkout --detach origin/master

     git checkout --force --detach origin/master



   At this point you might want to patch the sources again or set/modify a build

   tag, as explained earlier; afterwards adjust the build configuration to the

   new codebase and build your next kernel::

   tag, as explained earlier. Afterwards adjust the build configuration to the

   new codebase using olddefconfig, which will now adjust the configuration file

   you prepared earlier using localmodconfig  (~/linux/.config) for your next

   kernel::



     # reminder: if you want to apply patches, do it at this point

     # reminder: you might want to update your build tag at this point

     make olddefconfig



   Now build your kernel::



     make -j $(nproc --all)



   Install the kernel as outlined above::

   Afterwards install the kernel as outlined above::



     command -v installkernel && sudo make modules_install install
@@ -584,10 +589,10 @@ versions and individual commits at hand at any time:: 
    curl -L \

      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/clone.bundle \

      -o linux-stable.git.bundle

    git clone clone.bundle ~/linux/

    git clone linux-stable.git.bundle ~/linux/

    rm linux-stable.git.bundle

    cd ~/linux/

    git remote set-url origin

    git remote set-url origin \

      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

    git fetch origin

    git checkout --detach origin/master