-4) Select e-mail destination.
+4) Style check your changes.
+
+Check your patch for basic style violations, details of which can be
+found in Documentation/CodingStyle. Failure to do so simply wastes
+the reviewers time and will get your patch rejected, probably
+without even being read.
+
+At a minimum you should check your patches with the patch style
+checker prior to submission (scripts/checkpatch.pl). You should
+be able to justify all violations that remain in your patch.
+
+
+
+5) Select e-mail destination.
Look through the MAINTAINERS file and the source code, and determine
if your change applies to a specific subsystem of the kernel, with
Linus Torvalds is the final arbiter of all changes accepted into the
-Linux kernel. His e-mail address is <torvalds@osdl.org>. He gets
-a lot of e-mail, so typically you should do your best to -avoid- sending
-him e-mail.
+Linux kernel. His e-mail address is <torvalds@linux-foundation.org>.
+He gets a lot of e-mail, so typically you should do your best to -avoid-
+sending him e-mail.
Patches which are bug fixes, are "obvious" changes, or similarly
require little discussion should be sent or CC'd to Linus. Patches
-5) Select your CC (e-mail carbon copy) list.
+6) Select your CC (e-mail carbon copy) list.
Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.
copy the maintainer when you change their code.
For small patches you may want to CC the Trivial Patch Monkey
-trivial@kernel.org managed by Adrian Bunk; which collects "trivial"
+trivial@kernel.org managed by Jesper Juhl; which collects "trivial"
patches. Trivial patches must qualify for one of the following rules:
Spelling fixes in documentation
Spelling fixes which could break grep(1)
since people copy, as long as it's trivial)
Any fix by the author/maintainer of the file (ie. patch monkey
in re-transmission mode)
-URL: <http://www.kernel.org/pub/linux/kernel/people/bunk/trivial/>
-
+URL: <http://www.kernel.org/pub/linux/kernel/people/juhl/trivial/>
-6) No MIME, no links, no compression, no attachments. Just plain text.
+7) No MIME, no links, no compression, no attachments. Just plain text.
Linus and other kernel developers need to be able to read and comment
on the changes you are submitting. It is important for a kernel
Exception: If your mailer is mangling patches then someone may ask
you to re-send them using MIME.
+See Documentation/email-clients.txt for hints about configuring
+your e-mail client so that it sends your patches untouched.
+8) E-mail size.
-7) E-mail size.
-
-When sending patches to Linus, always follow step #6.
+When sending patches to Linus, always follow step #7.
Large changes are not appropriate for mailing lists, and some
maintainers. If your patch, uncompressed, exceeds 40 kB in size,
-8) Name your kernel version.
+9) Name your kernel version.
It is important to note, either in the subject line or in the patch
description, the kernel version to which this patch applies.
-9) Don't get discouraged. Re-submit.
+10) Don't get discouraged. Re-submit.
After you have submitted your change, be patient and wait. If Linus
likes your change and applies it, it will appear in the next version
-10) Include PATCH in the subject
+11) Include PATCH in the subject
Due to high e-mail traffic to Linus, and to linux-kernel, it is common
convention to prefix your subject line with [PATCH]. This lets Linus
-11) Sign your work
+12) Sign your work
To improve tracking of who did what, especially with patches that can
percolate to their final resting place in the kernel through several
point out some special detail about the sign-off.
-12) The canonical patch format
+13) When to use Acked-by: and Cc:
+
+The Signed-off-by: tag indicates that the signer was involved in the
+development of the patch, or that he/she was in the patch's delivery path.
+
+If a person was not directly involved in the preparation or handling of a
+patch but wishes to signify and record their approval of it then they can
+arrange to have an Acked-by: line added to the patch's changelog.
+
+Acked-by: is often used by the maintainer of the affected code when that
+maintainer neither contributed to nor forwarded the patch.
+
+Acked-by: is not as formal as Signed-off-by:. It is a record that the acker
+has at least reviewed the patch and has indicated acceptance. Hence patch
+mergers will sometimes manually convert an acker's "yep, looks good to me"
+into an Acked-by:.
+
+Acked-by: does not necessarily indicate acknowledgement of the entire patch.
+For example, if a patch affects multiple subsystems and has an Acked-by: from
+one subsystem maintainer then this usually indicates acknowledgement of just
+the part which affects that maintainer's code. Judgement should be used here.
+When in doubt people should refer to the original discussion in the mailing
+list archives.
+
+If a person has had the opportunity to comment on a patch, but has not
+provided such comments, you may optionally add a "Cc:" tag to the patch.
+This is the only tag which might be added without an explicit action by the
+person it names. This tag documents that potentially interested parties
+have been included in the discussion
+
+
+14) Using Test-by: and Reviewed-by:
+
+A Tested-by: tag indicates that the patch has been successfully tested (in
+some environment) by the person named. This tag informs maintainers that
+some testing has been performed, provides a means to locate testers for
+future patches, and ensures credit for the testers.
+
+Reviewed-by:, instead, indicates that the patch has been reviewed and found
+acceptable according to the Reviewer's Statement:
+
+ Reviewer's statement of oversight
+
+ By offering my Reviewed-by: tag, I state that:
+
+ (a) I have carried out a technical review of this patch to
+ evaluate its appropriateness and readiness for inclusion into
+ the mainline kernel.
+
+ (b) Any problems, concerns, or questions relating to the patch
+ have been communicated back to the submitter. I am satisfied
+ with the submitter's response to my comments.
+
+ (c) While there may be things that could be improved with this
+ submission, I believe that it is, at this time, (1) a
+ worthwhile modification to the kernel, and (2) free of known
+ issues which would argue against its inclusion.
+
+ (d) While I have reviewed the patch and believe it to be sound, I
+ do not (unless explicitly stated elsewhere) make any
+ warranties or guarantees that it will achieve its stated
+ purpose or function properly in any given situation.
+
+A Reviewed-by tag is a statement of opinion that the patch is an
+appropriate modification of the kernel without any remaining serious
+technical issues. Any interested reviewer (who has done the work) can
+offer a Reviewed-by tag for a patch. This tag serves to give credit to
+reviewers and to inform maintainers of the degree of review which has been
+done on the patch. Reviewed-by: tags, when supplied by reviewers known to
+understand the subject area and to perform thorough reviews, will normally
+increase the liklihood of your patch getting into the kernel.
+
+
+15) The canonical patch format
The canonical patch subject line is:
The "summary phrase" in the email's Subject should concisely
describe the patch which that email contains. The "summary
phrase" should not be a filename. Do not use the same "summary
-phrase" for every patch in a whole patch series.
+phrase" for every patch in a whole patch series (where a "patch
+series" is an ordered sequence of multiple, related patches).
Bear in mind that the "summary phrase" of your email becomes
a globally-unique identifier for that patch. It propagates
Nuff said. If your code deviates too much from this, it is likely
to be rejected without further review, and without comment.
+One significant exception is when moving code from one file to
+another -- in this case you should not modify the moved code at all in
+the same patch which moves it. This clearly delineates the act of
+moving the code and your changes. This greatly aids review of the
+actual differences and allows tools to better track the history of
+the code itself.
+
+Check your patches with the patch style checker prior to submission
+(scripts/checkpatch.pl). The style checker should be viewed as
+a guide not as the final word. If your code looks better with
+a violation then its probably best left alone.
+
+The checker reports at three levels:
+ - ERROR: things that are very likely to be wrong
+ - WARNING: things requiring careful review
+ - CHECK: things requiring thought
+
+You should be able to justify all violations that remain in your
+patch.
+
2) #ifdefs are ugly
limitations, and under gcc they are as cheap as macros.
Macros should only be used for cases where a static inline is clearly
-suboptimal [there a few, isolated cases of this in fast paths],
+suboptimal [there are a few, isolated cases of this in fast paths],
or where it is impossible to use a static inline function [such as
string-izing].
<http://marc.theaimsgroup.com/?l=linux-kernel&m=112112749912944&w=2>
Kernel Documentation/CodingStyle:
- <http://sosdg.org/~coywolf/lxr/source/Documentation/CodingStyle>
+ <http://users.sosdg.org/~qiyong/lxr/source/Documentation/CodingStyle>
Linus Torvalds's mail on the canonical patch format:
<http://lkml.org/lkml/2005/4/7/183>
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff