summaryrefslogtreecommitdiff
path: root/Documentation/SubmittingPatches
diff options
context:
space:
mode:
authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /Documentation/SubmittingPatches
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
downloadFOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz
FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2
FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'Documentation/SubmittingPatches')
-rw-r--r--Documentation/SubmittingPatches736
1 files changed, 736 insertions, 0 deletions
diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
new file mode 100644
index 00000000..4468ce24
--- /dev/null
+++ b/Documentation/SubmittingPatches
@@ -0,0 +1,736 @@
+
+ How to Get Your Change Into the Linux Kernel
+ or
+ Care And Operation Of Your Linus Torvalds
+
+
+
+For a person or company who wishes to submit a change to the Linux
+kernel, the process can sometimes be daunting if you're not familiar
+with "the system." This text is a collection of suggestions which
+can greatly increase the chances of your change being accepted.
+
+Read Documentation/SubmitChecklist for a list of items to check
+before submitting code. If you are submitting a driver, also read
+Documentation/SubmittingDrivers.
+
+
+
+--------------------------------------------
+SECTION 1 - CREATING AND SENDING YOUR CHANGE
+--------------------------------------------
+
+
+
+1) "diff -up"
+------------
+
+Use "diff -up" or "diff -uprN" to create patches.
+
+All changes to the Linux kernel occur in the form of patches, as
+generated by diff(1). When creating your patch, make sure to create it
+in "unified diff" format, as supplied by the '-u' argument to diff(1).
+Also, please use the '-p' argument which shows which C function each
+change is in - that makes the resultant diff a lot easier to read.
+Patches should be based in the root kernel source directory,
+not in any lower subdirectory.
+
+To create a patch for a single file, it is often sufficient to do:
+
+ SRCTREE= linux-2.6
+ MYFILE= drivers/net/mydriver.c
+
+ cd $SRCTREE
+ cp $MYFILE $MYFILE.orig
+ vi $MYFILE # make your change
+ cd ..
+ diff -up $SRCTREE/$MYFILE{.orig,} > /tmp/patch
+
+To create a patch for multiple files, you should unpack a "vanilla",
+or unmodified kernel source tree, and generate a diff against your
+own source tree. For example:
+
+ MYSRC= /devel/linux-2.6
+
+ tar xvfz linux-2.6.12.tar.gz
+ mv linux-2.6.12 linux-2.6.12-vanilla
+ diff -uprN -X linux-2.6.12-vanilla/Documentation/dontdiff \
+ linux-2.6.12-vanilla $MYSRC > /tmp/patch
+
+"dontdiff" is a list of files which are generated by the kernel during
+the build process, and should be ignored in any diff(1)-generated
+patch. The "dontdiff" file is included in the kernel tree in
+2.6.12 and later. For earlier kernel versions, you can get it
+from <http://www.xenotime.net/linux/doc/dontdiff>.
+
+Make sure your patch does not include any extra files which do not
+belong in a patch submission. Make sure to review your patch -after-
+generated it with diff(1), to ensure accuracy.
+
+If your changes produce a lot of deltas, you may want to look into
+splitting them into individual patches which modify things in
+logical stages. This will facilitate easier reviewing by other
+kernel developers, very important if you want your patch accepted.
+There are a number of scripts which can aid in this:
+
+Quilt:
+http://savannah.nongnu.org/projects/quilt
+
+Andrew Morton's patch scripts:
+http://userweb.kernel.org/~akpm/stuff/patch-scripts.tar.gz
+Instead of these scripts, quilt is the recommended patch management
+tool (see above).
+
+
+
+2) Describe your changes.
+
+Describe the technical detail of the change(s) your patch includes.
+
+Be as specific as possible. The WORST descriptions possible include
+things like "update driver X", "bug fix for driver X", or "this patch
+includes updates for subsystem X. Please apply."
+
+The maintainer will thank you if you write your patch description in a
+form which can be easily pulled into Linux's source code management
+system, git, as a "commit log". See #15, below.
+
+If your description starts to get long, that's a sign that you probably
+need to split up your patch. See #3, next.
+
+When you submit or resubmit a patch or patch series, include the
+complete patch description and justification for it. Don't just
+say that this is version N of the patch (series). Don't expect the
+patch merger to refer back to earlier patch versions or referenced
+URLs to find the patch description and put that into the patch.
+I.e., the patch (series) and its description should be self-contained.
+This benefits both the patch merger(s) and reviewers. Some reviewers
+probably didn't even receive earlier versions of the patch.
+
+If the patch fixes a logged bug entry, refer to that bug entry by
+number and URL.
+
+
+3) Separate your changes.
+
+Separate _logical changes_ into a single patch file.
+
+For example, if your changes include both bug fixes and performance
+enhancements for a single driver, separate those changes into two
+or more patches. If your changes include an API update, and a new
+driver which uses that new API, separate those into two patches.
+
+On the other hand, if you make a single change to numerous files,
+group those changes into a single patch. Thus a single logical change
+is contained within a single patch.
+
+If one patch depends on another patch in order for a change to be
+complete, that is OK. Simply note "this patch depends on patch X"
+in your patch description.
+
+If you cannot condense your patch set into a smaller set of patches,
+then only post say 15 or so at a time and wait for review and integration.
+
+
+
+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
+an assigned maintainer. If so, e-mail that person.
+
+If no maintainer is listed, or the maintainer does not respond, send
+your patch to the primary Linux kernel developer's mailing list,
+linux-kernel@vger.kernel.org. Most kernel developers monitor this
+e-mail list, and can comment on your changes.
+
+
+Do not send more than 15 patches at once to the vger mailing lists!!!
+
+
+Linus Torvalds is the final arbiter of all changes accepted into the
+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
+which require discussion or do not have a clear advantage should
+usually be sent first to linux-kernel. Only after the patch is
+discussed should the patch then be submitted to Linus.
+
+
+
+6) Select your CC (e-mail carbon copy) list.
+
+Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.
+
+Other kernel developers besides Linus need to be aware of your change,
+so that they may comment on it and offer code review and suggestions.
+linux-kernel is the primary Linux kernel developer mailing list.
+Other mailing lists are available for specific subsystems, such as
+USB, framebuffer devices, the VFS, the SCSI subsystem, etc. See the
+MAINTAINERS file for a mailing list that relates specifically to
+your change.
+
+Majordomo lists of VGER.KERNEL.ORG at:
+ <http://vger.kernel.org/vger-lists.html>
+
+If changes affect userland-kernel interfaces, please send
+the MAN-PAGES maintainer (as listed in the MAINTAINERS file)
+a man-pages patch, or at least a notification of the change,
+so that some information makes its way into the manual pages.
+
+Even if the maintainer did not respond in step #5, make sure to ALWAYS
+copy the maintainer when you change their code.
+
+For small patches you may want to CC the Trivial Patch Monkey
+trivial@kernel.org which collects "trivial" patches. Have a look
+into the MAINTAINERS file for its current manager.
+Trivial patches must qualify for one of the following rules:
+ Spelling fixes in documentation
+ Spelling fixes which could break grep(1)
+ Warning fixes (cluttering with useless warnings is bad)
+ Compilation fixes (only if they are actually correct)
+ Runtime fixes (only if they actually fix things)
+ Removing use of deprecated functions/macros (eg. check_region)
+ Contact detail and documentation fixes
+ Non-portable code replaced by portable code (even in arch-specific,
+ 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)
+
+
+
+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
+developer to be able to "quote" your changes, using standard e-mail
+tools, so that they may comment on specific portions of your code.
+
+For this reason, all patches should be submitting e-mail "inline".
+WARNING: Be wary of your editor's word-wrap corrupting your patch,
+if you choose to cut-n-paste your patch.
+
+Do not attach the patch as a MIME attachment, compressed or not.
+Many popular e-mail applications will not always transmit a MIME
+attachment as plain text, making it impossible to comment on your
+code. A MIME attachment also takes Linus a bit more time to process,
+decreasing the likelihood of your MIME-attached change being accepted.
+
+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.
+
+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 300 kB in size,
+it is preferred that you store your patch on an Internet-accessible
+server, and provide instead a URL (link) pointing to your patch.
+
+
+
+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.
+
+If the patch does not apply cleanly to the latest kernel version,
+Linus will not apply it.
+
+
+
+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
+of the kernel that he releases.
+
+However, if your change doesn't appear in the next version of the
+kernel, there could be any number of reasons. It's YOUR job to
+narrow down those reasons, correct what was wrong, and submit your
+updated change.
+
+It is quite common for Linus to "drop" your patch without comment.
+That's the nature of the system. If he drops your patch, it could be
+due to
+* Your patch did not apply cleanly to the latest kernel version.
+* Your patch was not sufficiently discussed on linux-kernel.
+* A style issue (see section 2).
+* An e-mail formatting issue (re-read this section).
+* A technical problem with your change.
+* He gets tons of e-mail, and yours got lost in the shuffle.
+* You are being annoying.
+
+When in doubt, solicit comments on linux-kernel mailing list.
+
+
+
+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
+and other kernel developers more easily distinguish patches from other
+e-mail discussions.
+
+
+
+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
+layers of maintainers, we've introduced a "sign-off" procedure on
+patches that are being emailed around.
+
+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.)
+
+Some people also put extra tags at the end. They'll just be ignored for
+now, but you can do this to mark internal company procedures or just
+point out some special detail about the sign-off.
+
+If you are a subsystem or branch maintainer, sometimes you need to slightly
+modify patches you receive in order to merge them, because the code is not
+exactly the same in your tree and the submitters'. If you stick strictly to
+rule (c), you should ask the submitter to rediff, but this is a totally
+counter-productive waste of time and energy. Rule (b) allows you to adjust
+the code, but then it is very impolite to change one submitter's code and
+make him endorse your bugs. To solve this problem, it is recommended that
+you add a line between the last Signed-off-by header and yours, indicating
+the nature of your changes. While there is nothing mandatory about this, it
+seems like prepending the description with your mail and/or name, all
+enclosed in square brackets, is noticeable enough to make it obvious that
+you are responsible for last-minute changes. Example :
+
+ Signed-off-by: Random J Developer <random@developer.example.org>
+ [lucky@maintainer.example.org: struct foo moved from foo.c to foo.h]
+ Signed-off-by: Lucky K Maintainer <lucky@maintainer.example.org>
+
+This practise is particularly helpful if you maintain a stable branch and
+want at the same time to credit the author, track changes, merge the fix,
+and protect the submitter from complaints. Note that under no circumstances
+can you change the author's identity (the From header), as it is the one
+which appears in the changelog.
+
+Special note to back-porters: It seems to be a common and useful practise
+to insert an indication of the origin of a patch at the top of the commit
+message (just after the subject line) to facilitate tracking. For instance,
+here's what we see in 2.6-stable :
+
+ Date: Tue May 13 19:10:30 2008 +0000
+
+ SCSI: libiscsi regression in 2.6.25: fix nop timer handling
+
+ commit 4cf1043593db6a337f10e006c23c69e5fc93e722 upstream
+
+And here's what appears in 2.4 :
+
+ Date: Tue May 13 22:12:27 2008 +0200
+
+ wireless, airo: waitbusy() won't delay
+
+ [backport of 2.6 commit b7acbdfbd1f277c1eb23f344f899cfa4cd0bf36a]
+
+Whatever the format, this information provides a valuable help to people
+tracking your trees, and to people trying to trouble-shoot bugs in your
+tree.
+
+
+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 Reported-by:, Tested-by: and Reviewed-by:
+
+If this patch fixes a problem reported by somebody else, consider adding a
+Reported-by: tag to credit the reporter for their contribution. Please
+note that this tag should not be added without the reporter's permission,
+especially if the problem was not reported in a public forum. That said,
+if we diligently credit our bug reporters, they will, hopefully, be
+inspired to help us again in the future.
+
+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 likelihood of your patch getting into the kernel.
+
+
+15) The canonical patch format
+
+The canonical patch subject line is:
+
+ Subject: [PATCH 001/123] subsystem: summary phrase
+
+The canonical patch message body contains the following:
+
+ - A "from" line specifying the patch author.
+
+ - An empty line.
+
+ - The body of the explanation, which will be copied to the
+ permanent changelog to describe this patch.
+
+ - The "Signed-off-by:" lines, described above, which will
+ also go in the changelog.
+
+ - A marker line containing simply "---".
+
+ - Any additional comments not suitable for the changelog.
+
+ - The actual patch (diff output).
+
+The Subject line format makes it very easy to sort the emails
+alphabetically by subject line - pretty much any email reader will
+support that - since because the sequence number is zero-padded,
+the numerical and alphabetic sort is the same.
+
+The "subsystem" in the email's Subject should identify which
+area or subsystem of the kernel is being patched.
+
+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 (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 all the way
+into the git changelog. The "summary phrase" may later be used in
+developer discussions which refer to the patch. People will want to
+google for the "summary phrase" to read discussion regarding that
+patch. It will also be the only thing that people may quickly see
+when, two or three months later, they are going through perhaps
+thousands of patches using tools such as "gitk" or "git log
+--oneline".
+
+For these reasons, the "summary" must be no more than 70-75
+characters, and it must describe both what the patch changes, as well
+as why the patch might be necessary. It is challenging to be both
+succinct and descriptive, but that is what a well-written summary
+should do.
+
+The "summary phrase" may be prefixed by tags enclosed in square
+brackets: "Subject: [PATCH tag] <summary phrase>". The tags are not
+considered part of the summary phrase, but describe how the patch
+should be treated. Common tags might include a version descriptor if
+the multiple versions of the patch have been sent out in response to
+comments (i.e., "v1, v2, v3"), or "RFC" to indicate a request for
+comments. If there are four patches in a patch series the individual
+patches may be numbered like this: 1/4, 2/4, 3/4, 4/4. This assures
+that developers understand the order in which the patches should be
+applied and that they have reviewed or applied all of the patches in
+the patch series.
+
+A couple of example Subjects:
+
+ Subject: [patch 2/5] ext2: improve scalability of bitmap searching
+ Subject: [PATCHv2 001/207] x86: fix eflags tracking
+
+The "from" line must be the very first line in the message body,
+and has the form:
+
+ From: Original Author <author@example.com>
+
+The "from" line specifies who will be credited as the author of the
+patch in the permanent changelog. If the "from" line is missing,
+then the "From:" line from the email header will be used to determine
+the patch author in the changelog.
+
+The explanation body will be committed to the permanent source
+changelog, so should make sense to a competent reader who has long
+since forgotten the immediate details of the discussion that might
+have led to this patch. Including symptoms of the failure which the
+patch addresses (kernel log messages, oops messages, etc.) is
+especially useful for people who might be searching the commit logs
+looking for the applicable patch. If a patch fixes a compile failure,
+it may not be necessary to include _all_ of the compile failures; just
+enough that it is likely that someone searching for the patch can find
+it. As in the "summary phrase", it is important to be both succinct as
+well as descriptive.
+
+The "---" marker line serves the essential purpose of marking for patch
+handling tools where the changelog message ends.
+
+One good use for the additional comments after the "---" marker is for
+a diffstat, to show what files have changed, and the number of
+inserted and deleted lines per file. A diffstat is especially useful
+on bigger patches. Other comments relevant only to the moment or the
+maintainer, not suitable for the permanent changelog, should also go
+here. A good example of such comments might be "patch changelogs"
+which describe what has changed between the v1 and v2 version of the
+patch.
+
+If you are going to include a diffstat after the "---" marker, please
+use diffstat options "-p 1 -w 70" so that filenames are listed from
+the top of the kernel source tree and don't use too much horizontal
+space (easily fit in 80 columns, maybe with some indentation).
+
+See more details on the proper patch format in the following
+references.
+
+
+16) Sending "git pull" requests (from Linus emails)
+
+Please write the git repo address and branch name alone on the same line
+so that I can't even by mistake pull from the wrong branch, and so
+that a triple-click just selects the whole thing.
+
+So the proper format is something along the lines of:
+
+ "Please pull from
+
+ git://jdelvare.pck.nerim.net/jdelvare-2.6 i2c-for-linus
+
+ to get these changes:"
+
+so that I don't have to hunt-and-peck for the address and inevitably
+get it wrong (actually, I've only gotten it wrong a few times, and
+checking against the diffstat tells me when I get it wrong, but I'm
+just a lot more comfortable when I don't have to "look for" the right
+thing to pull, and double-check that I have the right branch-name).
+
+
+Please use "git diff -M --stat --summary" to generate the diffstat:
+the -M enables rename detection, and the summary enables a summary of
+new/deleted or renamed files.
+
+With rename detection, the statistics are rather different [...]
+because git will notice that a fair number of the changes are renames.
+
+-----------------------------------
+SECTION 2 - HINTS, TIPS, AND TRICKS
+-----------------------------------
+
+This section lists many of the common "rules" associated with code
+submitted to the kernel. There are always exceptions... but you must
+have a really good reason for doing so. You could probably call this
+section Linus Computer Science 101.
+
+
+
+1) Read Documentation/CodingStyle
+
+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
+
+Code cluttered with ifdefs is difficult to read and maintain. Don't do
+it. Instead, put your ifdefs in a header, and conditionally define
+'static inline' functions, or macros, which are used in the code.
+Let the compiler optimize away the "no-op" case.
+
+Simple example, of poor code:
+
+ dev = alloc_etherdev (sizeof(struct funky_private));
+ if (!dev)
+ return -ENODEV;
+ #ifdef CONFIG_NET_FUNKINESS
+ init_funky_net(dev);
+ #endif
+
+Cleaned-up example:
+
+(in header)
+ #ifndef CONFIG_NET_FUNKINESS
+ static inline void init_funky_net (struct net_device *d) {}
+ #endif
+
+(in the code itself)
+ dev = alloc_etherdev (sizeof(struct funky_private));
+ if (!dev)
+ return -ENODEV;
+ init_funky_net(dev);
+
+
+
+3) 'static inline' is better than a macro
+
+Static inline functions are greatly preferred over macros.
+They provide type safety, have no length limitations, no formatting
+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 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].
+
+'static inline' is preferred over 'static __inline__', 'extern inline',
+and 'extern __inline__'.
+
+
+
+4) Don't over-design.
+
+Don't try to anticipate nebulous future cases which may or may not
+be useful: "Make it as simple as you can, and no simpler."
+
+
+
+----------------------
+SECTION 3 - REFERENCES
+----------------------
+
+Andrew Morton, "The perfect patch" (tpp).
+ <http://userweb.kernel.org/~akpm/stuff/tpp.txt>
+
+Jeff Garzik, "Linux kernel patch submission format".
+ <http://linux.yyz.us/patch-format.html>
+
+Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer".
+ <http://www.kroah.com/log/linux/maintainer.html>
+ <http://www.kroah.com/log/linux/maintainer-02.html>
+ <http://www.kroah.com/log/linux/maintainer-03.html>
+ <http://www.kroah.com/log/linux/maintainer-04.html>
+ <http://www.kroah.com/log/linux/maintainer-05.html>
+
+NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people!
+ <http://marc.theaimsgroup.com/?l=linux-kernel&m=112112749912944&w=2>
+
+Kernel 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>
+
+Andi Kleen, "On submitting kernel patches"
+ Some strategies to get difficult or controversial changes in.
+ http://halobates.de/on-submitting-patches.pdf
+
+--