Re: How to switch kernel customizations from 2.6.15.6 to 2.6.16?

[Shawn Pearce <spearce@spearce.org>]

Matt McCutchen <hashproduct@verizon.net> wrote:
> Dear git people,
> 
> I made a customized Linux kernel based on 2.6.15.6 by cloning the stable
> 2.6.15 kernel repository (which was then at version 2.6.15.6) and making
> several commits.  Now I would like a Linux kernel based on 2.6.16 with
> the same customizations.  This seems to be a very simple task, but I
> have been trying various combinations of git commands for several days
> and have not figured out how to do it.
> 
> I believe that means I should pull the 2.6.16 kernel into the "origin"
> branch and then rebase the "master" branch, merging my customizations
> with 2.6.16.  To this end, I switched my remote file to point to the
> 2.6.16 stable repository and tried to pull.  The result was not what I
> wanted.  The situation is complicated by the fact that 2.6.15.6 is not
> an ancestor of 2.6.16.  The warning in the man page about branches that
> are modified nonlinearly seems to apply.
> 
> How do I make my customized 2.6.16 kernel?

I think you want to use `git-fetch --force` to download origin but
not immediately merge it yet.  This will bypass the not-an-ancestor
check you are running into.

Then you can perform the rebase yourself with:

	# Export your local changes into a series of patches.
	#
	git-format-patch -k --stdout --full-index v2.6.16.6 >changes.mbox

	# Checkout the new origin (2.6.16) into master.
	#
	git-reset --hard origin

	# Now apply your patches.
	#
	git-am --binary -3 changes.mbox

If you get merge conflicts fix them up and restart with
`git-am --resolved`.


Note this is the logic of `git-rebase` except it doesn't require
you to actually have a common ancestor, while `git-rebase` does.

-- 
Shawn.