Adding patches through git

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WIP incomplete

Add kernel patches to be committed to the Preware feed by following this guide.

Prerequisites

  • SSH key generated, with the id_dsa.pub authorised for commital on git.webos-internals.org (rwhitby is able to do this)
  • GPL compliant patch to submit (preferably with a .patch extension)

Initialising your local repository

  • You will need to pull down the kernel/patches repository as a starting point with

<source lang="text">git clone git@git.webos-internals.org:kernels/patches.git</source>

A worked example is as follows:

<source lang="text"> mason~/kernels$ git clone git@git.webos-internals.org:kernels/patches.git Initialized empty Git repository in /home/sbromwich/kernels/patches/.git/ Enter passphrase for key '/home/sbromwich/.ssh/id_dsa': remote: Counting objects: 70, done. remote: Compressing objects: 100% (68/68), done. remote: Total 70 (delta 23), reused 0 (delta 0) Receiving objects: 100% (70/70), 15.21 KiB, done. Resolving deltas: 100% (23/23), done. mason~/kernels$ ls patches mason~/kernels$ ls -l total 4 drwxr-xr-x 5 sbromwich sbromwich 4096 Apr 22 22:17 patches mason~/kernels$ cd patches/ mason~/kernels/patches$ ls LICENSE overclocking sensors mason~/kernels/patches$ ls -l total 12 -rw-r--r-- 1 sbromwich sbromwich 88 Apr 22 22:17 LICENSE drwxr-xr-x 2 sbromwich sbromwich 4096 Apr 22 22:17 overclocking drwxr-xr-x 2 sbromwich sbromwich 4096 Apr 22 22:17 sensors mason~/kernels/patches$ </source>

  • Create a directory for your patch(es) and copy them in there.

Tag patches and submit to git

  • Find the next available git tag with

<source lang="text">git tag -l</source>

In the following case, the next tag is v1.4.1-10:

<source lang="text"> mason~/kernels/patches/prcm$ git tag -l v1.4.0-0 v1.4.0-1 v1.4.1-1 v1.4.1-2 v1.4.1-3 v1.4.1-4 v1.4.1-5 v1.4.1-6 v1.4.1-7 v1.4.1-8 v1.4.1-9 mason~/kernels/patches/prcm$ </source>

  • Tag the files with a meaningful commit message and the tag from the previous step:

<source lang="text"> mason~/kernels/patches/prcm$ git tag -a -m "PRCM resume from suspend fix/kludge" v1.4.1-10 mason~/kernels/patches/prcm$ </source>

  • Send the tagged files to the upstream repository with

<source lang="text">git push ; git push --tags</source>

For example:

<source lang="text"> mason~/kernels/patches/prcm$ git push ; git push --tags Enter passphrase for key '/home/sbromwich/.ssh/id_dsa': Everything up-to-date Enter passphrase for key '/home/sbromwich/.ssh/id_dsa': Counting objects: 1, done. Writing objects: 100% (1/1), 187 bytes, done. Total 1 (delta 0), reused 0 (delta 0) To git@git.webos-internals.org:kernels/patches.git

* [new tag]         v1.4.1-10 -> v1.4.1-10

mason~/kernels/patches/prcm$ </source>

Commit the tagged files to git

Committing the tagged files is the following three step process:

  • git add filenames
  • git commit -m "commit message" filenames
  • git push

Worked example:

<source lang="text"> mason~/kernels/patches/prcm$ git add * mason~/kernels/patches/prcm$ git commit -m "PRCM resume from suspend fix/kludge" * Created commit 16fbb97: PRCM resume from suspend fix/kludge

3 files changed, 84 insertions(+), 0 deletions(-)
create mode 100644 prcm/README
create mode 100644 prcm/prcm_clk.c.diff
create mode 100644 prcm/proc_pwr.c.diff

mason~/kernels/patches/prcm$ git push Enter passphrase for key '/home/sbromwich/.ssh/id_dsa': Counting objects: 7, done. Compressing objects: 100% (6/6), done. Writing objects: 100% (6/6), 1.96 KiB, done. Total 6 (delta 0), reused 0 (delta 0) To git@git.webos-internals.org:kernels/patches.git

  b949e1d..16fbb97  master -> master

mason~/kernels/patches/prcm$ </source>

Uh-oh, I screwed up a commit - how do I remove a file?

If you inadvertently commit a file in error, it is easy to remove with

<source lang="text"> git remove filename git commit -m "commit message" filename </source>

Worked example:

<source lang="text"> mason~/build/hardware/uber-kernel-pre/build$ git rm src-1.4.1-6/linux-2.6.24/.config rm 'hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/.config' mason~/build/hardware/uber-kernel-pre/build$ git commit -m "Removing .config that should not have been committed in the first place" src-1.4.1-6/linux-2.6.24/.config Created commit cd95fd3: Removing .config that should not have been committed in the first place

1 files changed, 0 insertions(+), 1892 deletions(-)
delete mode 100644 hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/.config

mason~/build/hardware/uber-kernel-pre/build$ </source>

If you have modified the file, you will need to force the commit with the -f flag, as follows:

<source lang="text"> mason~/build/hardware/uber-kernel-pre/build$ git rm -f src-1.4.1-6/linux-2.6.24/arch/arm/mach-omap3pe/prcm_pwr.c src-1.4.1-6/linux-2.6.24/include/linux/vermagic.h rm 'hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/arch/arm/mach-omap3pe/prcm_pwr.c' rm 'hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/include/linux/vermagic.h' mason~/build/hardware/uber-kernel-pre/build$ git commit -m "Removing commits that should not have been committed" src-1.4.1-6/linux-2.6.24/arch/arm/mach-omap3pe/prcm_pwr.c src-1.4.1-6/linux-2.6.24/include/linux/vermagic.h Created commit 73eb872: Removing commits that should not have been committed

2 files changed, 0 insertions(+), 1885 deletions(-)
delete mode 100644 hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/arch/arm/mach-omap3pe/prcm_pwr.c
delete mode 100644 hardware/uber-kernel-pre/build/src-1.4.1-6/linux-2.6.24/include/linux/vermagic.h

mason~/build/hardware/uber-kernel-pre/build$ </source>

git conceptual tutorial

An excellent conceptual tutorial on how git works is available at http://www.eecs.harvard.edu/~cduan/technical/git/ courtesy of Charles Duan.