Adding patches through git

From WebOS Internals
Jump to: navigation, search

WIP incomplete

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


  • SSH key generated, with the authorised for commital on (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
git clone

A worked example is as follows:

mason~/kernels$ git clone
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
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
  • 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
git tag -l

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

mason~/kernels/patches/prcm$ git tag -l
  • Tag the files with a meaningful commit message and the tag from the previous step:
mason~/kernels/patches/prcm$ git tag -a -m "PRCM resume from suspend fix/kludge" v1.4.1-10
  • Send the tagged files to the upstream repository with
git push ; git push --tags

For example:

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

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:

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)
   b949e1d..16fbb97  master -> master

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

git remove filename
git commit -m "commit message" filename

Worked example:

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

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

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

git conceptual tutorial

An excellent conceptual tutorial on how git works is available at courtesy of Charles Duan.