Contributions to openEuler kernel project
=========================================

Sign CLA
--------

Before submitting any Contributions to openEuler, you have to sign CLA.

See:
     https://openeuler.org/zh/cla.html
     https://openeuler.org/en/cla.html

Steps of submitting patches
---------------------------

1. Compile and test your patches successfully.
2. Generate patches
   Your patches should be based on top of latest openEuler branch, and should
   use git-format-patch to generate patches, and if it's a patchset, it's
   better to use --cover-letter option to describe what the patchset does.

   Using scripts/checkpatch.pl to make sure there's no coding style issue.

   And make sure your patch follow unified openEuler patch format describe
   below.

3. Send patch to openEuler mailing list
   Use this command to send patches to openEuler mailing list:

     git send-email *.patch -to="kernel@openeuler.org" --suppress-cc=all

   *NOTE*: that you must add --suppress-cc=all if you use git send-email,
   otherwise the email will be cced to the people in upstream community and mailing
   lists.

   *See*: How to send patches using git-send-email
    https://git-scm.com/docs/git-send-email

4. Mark "v1, v2, v3 ..." in your patch subject if you have multiple versions
   to send out.

   Use --subject-prefix="PATCH v2" option to add v2 tag for patchset.
     git format-patch --subject-prefix="PATCH v2" -1

   Subject examples:
     Subject: [PATCH v2 01/27] fork: fix some -Wmissing-prototypes warnings
     Subject: [PATCH v3] ext2: improve scalability of bitmap searching

5. Upstream your kernel patch to kernel community is strongly recommended.
   openEuler will sync up with kernel master timely.

6. Sign your work - the Developer’s Certificate of Origin
   As the same of upstream kernel community, you also need to sign your patch.

   See: https://www.kernel.org/doc/html/latest/process/submitting-patches.html

   The sign-off is a simple line at the end of the explanation for the patch,
   which certifies that you wrote it or otherwise have the right to pass it
   on as an open-source patch. The rules are pretty simple: if you can certify
   the below:

   Developer’s Certificate of Origin 1.1
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

     By making a contribution to this project, I certify that:

     (a) The contribution was created in whole or in part by me and I have
         the right to submit it under the open source license indicated in
         the file; or

     (b  The contribution is based upon previous work that, to the best of
         my knowledge, is covered under an appropriate open source license
         and I have the right under that license to submit that work with
         modifications, whether created in whole or in part by me, under
         the same open source license (unless I am permitted to submit under
         a different license), as indicated in the file; or

     (c) The contribution was provided directly to me by some other person
         who certified (a), (b) or (c) and I have not modified it.

     (d) I understand and agree that this project and the contribution are
         public and that a record of the contribution (including all personal
         information I submit with it, including my sign-off) is maintained
         indefinitely and may be redistributed consistent with this project
         or the open source license(s) involved.

   then you just add a line saying:

     Signed-off-by: Random J Developer <random@developer.example.org>

   using your real name (sorry, no pseudonyms or anonymous contributions.)

Use unified patch format
------------------------

Reasons:

1. long term maintainability
   openEuler will merge massive patches. If all patches are merged by casual
   changelog format without a unified format, the git log will be messy, and
   then it's hard to figure out the original patch.

2. kernel upgrade
   We definitely will upgrade our openEuler kernel in someday, using strict
   patch management will alleviate the pain to migrate patches during big upgrade.

3. easy for script parsing
   Keyword highlighting is necessary for script parsing.

Patch format definition
-----------------------

[M] stands for "mandatory"
[O] stands for "option"
$category can be: bug preparation, bugfix, perf, feature, doc, other...

If category is feature, then we also need to add feature name like below:
	category: feature
	feature: YYY (the feature name)

If the patch is related to CVE or bugzilla, then we need add the corresponding
tag like below (In general, it should include at least one of the following):
	CVE: $cve-id
	bugzilla: $bug-id

Additional changelog should include at least one of the flollwing:
	1) Why we should apply this patch
	2) What real problem in product does this patch resolved
	3) How could we reproduce this bug or how to test
	4) Other useful information for help to understand this patch or problem

The detail information is very useful for porting patch to another kenrel branch.

Example for mainline patch:

	mainline inclusion      [M]
	from $mainline-version  [M]
	commit $id              [M]
	category: $category     [M]
	bugzilla: $bug-id       [O]
	CVE: $cve-id            [O]

	additional changelog    [O]

	--------------------------------

	original changelog

	Signed-off-by: $yourname <$yourname@huawei.com>   [M]

	($mainline-version could be mainline-3.5, mainline-3.6, etc...)

Examples
--------

mainline inclusion
from mainline-4.10
commit 0becc0ae5b42828785b589f686725ff5bc3b9b25
category: bugfix
bugzilla: 3004
CVE: NA

The patch fixes a BUG_ON in the product: injecting single bit ECC error
to memory before system boot use hardware inject tools, which cause a
large amount of CMCI during system booting .

[    1.146580] mce: [Hardware Error]: Machine check events logged
[    1.152908] ------------[ cut here ]------------
[    1.157751] kernel BUG at kernel/timer.c:951!
[    1.162321] invalid opcode: 0000 [#1] SMP
...

-------------------------------------------------

original changelog

<original S-O-B>
Signed-off-by: Zhang San <zhangsan@huawei.com>
Tested-by: Li Si <lisi@huawei.com>

Email Client - Thunderbird Settings
-----------------------------------

If you are newly developer in the kernel community, it is highly recommended
to use thunderbird mail client.

1. Thunderbird Installation
   Get English version Thunderbird from http://www.mozilla.org/ and install
   it on your system。

   Download url: https://www.thunderbird.net/en-US/thunderbird/all/

2. Settings
   2.1 Use plain text format instead of HTML format
       Options -> Account Settings -> Composition & Addressing, do *NOT* select
       "Compose message in HTML format".

   2.2 Editor Settings
       Tools->Options->Advanced->Config editor.

       - To bring up the thunderbird's registry editor, and set:
         "mailnews.send_plaintext_flowed" to "false".
       - Disable HTML Format: Set "mail.identity.id1.compose_html" to "false".
       - Enable UTF8: Set "prefs.converted-to-utf8" to "true".
       - View message in UTF-8: Set "mailnews.view_default_charset" to "UTF-8".
       - Set mailnews.wraplength to 9999 for avoiding auto-wrap

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.