ubuntu-bugcontrol team mailing list archive

["Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>]

Hello everyone. I wanted to e-mail you to get your feedback on a
proposed draft for updating the end of the KernelBisection article
(which has been remarkably successful in enabling new and experienced
bisectors to bisect their own kernel regressions).

The high level for this proposed draft is that a common event for bug
reporters is they want to test a patch not available in an upstream
tree (ex. linux-stable). However, they tend to get quite confused on
what to do step-by-step (as I was when I was Googling it all out). I
didn't find any article with a comprehensive click-for-click example,
I had to pick out what I needed from a number of articles, and dig
through a ton that were largely useless or didn't apply.

Hence, while the proposed draft would fit the logical flow of the
article placed at the end, as when one has finished commit bisecting
and an upstream patch was submitted but not merged, it may be better
placed in a different article, but I haven't really found one at this
point.

What do you think?

-START-
= Testing a patch from upstream =

Lets assume you may have identified an upstream patch that hasn't been
commited to an upstream branch, and you would like to test it out. Let
us take as an example the following upstream patch:

testfix.patch
http://www.spinics.net/lists/linux-acpi/msg47755.html

Start copying from the line where it notes:
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c

to the last code line before the double dash:
 static int register_count;

Your patch file should exactly as shown, honoring all spaces, or lack thereof:
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 995e91b..b3032f8 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -85,7 +85,7 @@ module_param(allow_duplicates, bool, 0644);
  * For Windows 8 systems: if set ture and the GPU driver has
  * registered a backlight interface, skip registering ACPI video's.
  */
-static bool use_native_backlight = false;
+static bool use_native_backlight = true;
 module_param(use_native_backlight, bool, 0644);

 static int register_count;

save this file to your Desktop as testfix.patch. Then execute at a terminal:
git config --global user.email "you@xxxxxxxxxxx" && git config
--global user.name "Your Name" && git clone
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
~/Desktop/linux-stable && patch
~/Desktop/linux-stable/drivers/acpi/video.c ~/Desktop/testfix.patch &&
git add . && git commit

Now in the new window type: {{{
example }}}

press Ctrl+O -> Enter -> Ctrl+X. Then, type at a terminal:
git log -n 1 | grep commit

which should post the commit:
commit <COMMIT>

Use this commit in the below terminal command:
git checkout <COMMIT> && cp /boot/config-`uname -r` .config && yes ''
| make oldconfig && make-kpkg clean && CONCURRENCY_LEVEL=`getconf
_NPROCESSORS_ONLN` fakeroot make-kpkg --initrd
--append-to-version=-custom2 kernel_image kernel_headers && cd .. &&
sudo dpkg -i *.deb

If for whatever reason the new kernel doesn't boot, it may not be you
did something wrong, but just that it won't boot with this commit
applied.
-END-

Christopher M. Penalver
E-Mail: christopher.m.penalver@xxxxxxxxx