1 .. SPDX-License-Identifier: GPL-2.0
12 - designate your patch to a tree - ``[PATCH net]`` or ``[PATCH net-next]``
13 - for fixes the ``Fixes:`` tag is required, regardless of the tree
14 - don't post large series (> 15 patches), break them up
15 - don't repost your patches within one 24h period
20 It is a mailing list for all network-related Linux stuff. This
21 includes anything found under net/ (i.e. core code like IPv6) and
22 drivers/net (i.e. hardware specific drivers) in the Linux source tree.
24 Note that some subsystems (e.g. wireless drivers) which have a high
25 volume of traffic have their own specific mailing lists.
27 The netdev list is managed (like many other Linux mailing lists) through
28 VGER (http://vger.kernel.org/) with archives available at
29 https://lore.kernel.org/netdev/
31 Aside from subsystems like those mentioned above, all network-related
32 Linux development (i.e. RFC, review, comments, etc.) takes place on
35 How do the changes posted to netdev make their way into Linux?
36 --------------------------------------------------------------
37 There are always two trees (git repositories) in play. Both are
38 driven by David Miller, the main network maintainer. There is the
39 ``net`` tree, and the ``net-next`` tree. As you can probably guess from
40 the names, the ``net`` tree is for fixes to existing code already in the
41 mainline tree from Linus, and ``net-next`` is where the new code goes
42 for the future release. You can find the trees here:
44 - https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git
45 - https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
47 How often do changes from these trees make it to the mainline Linus tree?
48 -------------------------------------------------------------------------
49 To understand this, you need to know a bit of background information on
50 the cadence of Linux development. Each new release starts off with a
51 two week "merge window" where the main maintainers feed their new stuff
52 to Linus for merging into the mainline tree. After the two weeks, the
53 merge window is closed, and it is called/tagged ``-rc1``. No new
54 features get mainlined after this -- only fixes to the rc1 content are
55 expected. After roughly a week of collecting fixes to the rc1 content,
56 rc2 is released. This repeats on a roughly weekly basis until rc7
57 (typically; sometimes rc6 if things are quiet, or rc8 if things are in a
58 state of churn), and a week after the last vX.Y-rcN was done, the
59 official vX.Y is released.
61 Relating that to netdev: At the beginning of the 2-week merge window,
62 the ``net-next`` tree will be closed - no new changes/features. The
63 accumulated new content of the past ~10 weeks will be passed onto
64 mainline/Linus via a pull request for vX.Y -- at the same time, the
65 ``net`` tree will start accumulating fixes for this pulled content
68 An announcement indicating when ``net-next`` has been closed is usually
69 sent to netdev, but knowing the above, you can predict that in advance.
72 Do not send new ``net-next`` content to netdev during the
73 period during which ``net-next`` tree is closed.
75 RFC patches sent for review only are obviously welcome at any time
76 (use ``--subject-prefix='RFC net-next'`` with ``git format-patch``).
78 Shortly after the two weeks have passed (and vX.Y-rc1 is released), the
79 tree for ``net-next`` reopens to collect content for the next (vX.Y+1)
82 If you aren't subscribed to netdev and/or are simply unsure if
83 ``net-next`` has re-opened yet, simply check the ``net-next`` git
84 repository link above for any new networking-related commits. You may
85 also check the following website for the current status:
87 http://vger.kernel.org/~davem/net-next.html
89 The ``net`` tree continues to collect fixes for the vX.Y content, and is
90 fed back to Linus at regular (~weekly) intervals. Meaning that the
91 focus for ``net`` is on stabilization and bug fixes.
93 Finally, the vX.Y gets released, and the whole cycle starts over.
95 So where are we now in this cycle?
96 ----------------------------------
98 Load the mainline (Linus) page here:
100 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
102 and note the top of the "tags" section. If it is rc1, it is early in
103 the dev cycle. If it was tagged rc7 a week ago, then a release is
104 probably imminent. If the most recent tag is a final release tag
105 (without an ``-rcN`` suffix) - we are most likely in a merge window
106 and ``net-next`` is closed.
108 How can I tell the status of a patch I've sent?
109 -----------------------------------------------
110 Start by looking at the main patchworks queue for netdev:
112 https://patchwork.kernel.org/project/netdevbpf/list/
114 The "State" field will tell you exactly where things are at with your
115 patch. Patches are indexed by the ``Message-ID`` header of the emails
116 which carried them so if you have trouble finding your patch append
117 the value of ``Message-ID`` to the URL above.
119 Should I directly update patchwork state of my own patches?
120 -----------------------------------------------------------
121 It may be tempting to help the maintainers and update the state of your
122 own patches when you post a new version or spot a bug. Please do not do that.
123 Interfering with the patch status on patchwork will only cause confusion. Leave
124 it to the maintainer to figure out what is the most recent and current
125 version that should be applied. If there is any doubt, the maintainer
126 will reply and ask what should be done.
128 How long before my patch is accepted?
129 -------------------------------------
130 Generally speaking, the patches get triaged quickly (in less than
131 48h). But be patient, if your patch is active in patchwork (i.e. it's
132 listed on the project's patch list) the chances it was missed are close to zero.
133 Asking the maintainer for status updates on your
134 patch is a good way to ensure your patch is ignored or pushed to the
135 bottom of the priority list.
137 I made changes to only a few patches in a patch series should I resend only those changed?
138 ------------------------------------------------------------------------------------------
139 No, please resend the entire patch series and make sure you do number your
140 patches such that it is clear this is the latest and greatest set of patches
143 I submitted multiple versions of a patch series and it looks like a version other than the last one has been accepted, what should I do?
144 ----------------------------------------------------------------------------------------------------------------------------------------
145 There is no revert possible, once it is pushed out, it stays like that.
146 Please send incremental versions on top of what has been merged in order to fix
147 the patches the way they would look like if your latest patch series was to be
150 Are there special rules regarding stable submissions on netdev?
151 ---------------------------------------------------------------
152 While it used to be the case that netdev submissions were not supposed
153 to carry explicit ``CC: stable@vger.kernel.org`` tags that is no longer
154 the case today. Please follow the standard stable rules in
155 :ref:`Documentation/process/stable-kernel-rules.rst <stable_kernel_rules>`,
156 and make sure you include appropriate Fixes tags!
158 I found a bug that might have possible security implications or similar. Should I mail the main netdev maintainer off-list?
159 ---------------------------------------------------------------------------------------------------------------------------
160 No. The current netdev maintainer has consistently requested that
161 people use the mailing lists and not reach out directly. If you aren't
162 OK with that, then perhaps consider mailing security@kernel.org or
163 reading about http://oss-security.openwall.org/wiki/mailing-lists/distros
164 as possible alternative mechanisms.
166 How do I post corresponding changes to user space components?
167 -------------------------------------------------------------
168 User space code exercising kernel features should be posted
169 alongside kernel patches. This gives reviewers a chance to see
170 how any new interface is used and how well it works.
172 When user space tools reside in the kernel repo itself all changes
173 should generally come as one series. If series becomes too large
174 or the user space project is not reviewed on netdev include a link
175 to a public repo where user space patches can be seen.
177 In case user space tooling lives in a separate repository but is
178 reviewed on netdev (e.g. patches to ``iproute2`` tools) kernel and
179 user space patches should form separate series (threads) when posted
180 to the mailing list, e.g.::
182 [PATCH net-next 0/3] net: some feature cover letter
183 └─ [PATCH net-next 1/3] net: some feature prep
184 └─ [PATCH net-next 2/3] net: some feature do it
185 └─ [PATCH net-next 3/3] selftest: net: some feature
187 [PATCH iproute2-next] ip: add support for some feature
189 Posting as one thread is discouraged because it confuses patchwork
190 (as of patchwork 2.2.2).
192 Any other tips to help ensure my net/net-next patch gets OK'd?
193 --------------------------------------------------------------
194 Attention to detail. Re-read your own work as if you were the
195 reviewer. You can start with using ``checkpatch.pl``, perhaps even with
196 the ``--strict`` flag. But do not be mindlessly robotic in doing so.
197 If your change is a bug fix, make sure your commit log indicates the
198 end-user visible symptom, the underlying reason as to why it happens,
199 and then if necessary, explain why the fix proposed is the best way to
200 get things done. Don't mangle whitespace, and as is common, don't
201 mis-indent function arguments that span multiple lines. If it is your
202 first patch, mail it to yourself so you can test apply it to an
203 unpatched tree to confirm infrastructure didn't mangle it.
205 Finally, go back and read
206 :ref:`Documentation/process/submitting-patches.rst <submittingpatches>`
207 to be sure you are not repeating some common mistake documented there.
209 How do I indicate which tree (net vs. net-next) my patch should be in?
210 ----------------------------------------------------------------------
211 To help maintainers and CI bots you should explicitly mark which tree
212 your patch is targeting. Assuming that you use git, use the prefix
215 git format-patch --subject-prefix='PATCH net-next' start..finish
217 Use ``net`` instead of ``net-next`` (always lower case) in the above for
218 bug-fix ``net`` content.
220 How do I divide my work into patches?
221 -------------------------------------
223 Put yourself in the shoes of the reviewer. Each patch is read separately
224 and therefore should constitute a comprehensible step towards your stated
227 Avoid sending series longer than 15 patches. Larger series takes longer
228 to review as reviewers will defer looking at it until they find a large
229 chunk of time. A small series can be reviewed in a short time, so Maintainers
230 just do it. As a result, a sequence of smaller series gets merged quicker and
231 with better review coverage. Re-posting large series also increases the mailing
234 Is the comment style convention different for the networking content?
235 ---------------------------------------------------------------------
236 Yes, in a largely trivial way. Instead of this::
239 * foobar blah blah blah
240 * another line of text
243 it is requested that you make it look like this::
245 /* foobar blah blah blah
246 * another line of text
249 What is "reverse xmas tree"?
250 ----------------------------
252 Netdev has a convention for ordering local variables in functions.
253 Order the variable declaration lines longest to shortest, e.g.::
255 struct scatterlist *sg;
259 If there are dependencies between the variables preventing the ordering
260 move the initialization out of line.
262 I am working in existing code which uses non-standard formatting. Which formatting should I use?
263 ------------------------------------------------------------------------------------------------
264 Make your code follow the most recent guidelines, so that eventually all code
265 in the domain of netdev is in the preferred format.
267 I have received review feedback, when should I post a revised version of the patches?
268 -------------------------------------------------------------------------------------
269 Allow at least 24 hours to pass between postings. This will ensure reviewers
270 from all geographical locations have a chance to chime in. Do not wait
271 too long (weeks) between postings either as it will make it harder for reviewers
272 to recall all the context.
274 Make sure you address all the feedback in your new posting. Do not post a new
275 version of the code if the discussion about the previous version is still
276 ongoing, unless directly instructed by a reviewer.
278 What level of testing is expected before I submit my change?
279 ------------------------------------------------------------
280 At the very minimum your changes must survive an ``allyesconfig`` and an
281 ``allmodconfig`` build with ``W=1`` set without new warnings or failures.
283 Ideally you will have done run-time testing specific to your change,
284 and the patch series contains a set of kernel selftest for
285 ``tools/testing/selftests/net`` or using the KUnit framework.
287 You are expected to test your changes on top of the relevant networking
288 tree (``net`` or ``net-next``) and not e.g. a stable tree or ``linux-next``.
290 Can I reproduce the checks from patchwork on my local machine?
291 --------------------------------------------------------------
293 Checks in patchwork are mostly simple wrappers around existing kernel
294 scripts, the sources are available at:
296 https://github.com/kuba-moo/nipa/tree/master/tests
298 Running all the builds and checks locally is a pain, can I post my patches and have the patchwork bot validate them?
299 --------------------------------------------------------------------------------------------------------------------
301 No, you must ensure that your patches are ready by testing them locally
302 before posting to the mailing list. The patchwork build bot instance
303 gets overloaded very easily and netdev@vger really doesn't need more
304 traffic if we can help it.
306 netdevsim is great, can I extend it for my out-of-tree tests?
307 -------------------------------------------------------------
309 No, ``netdevsim`` is a test vehicle solely for upstream tests.
310 (Please add your tests under ``tools/testing/selftests/``.)
312 We also give no guarantees that ``netdevsim`` won't change in the future
313 in a way which would break what would normally be considered uAPI.
315 Is netdevsim considered a "user" of an API?
316 -------------------------------------------
318 Linux kernel has a long standing rule that no API should be added unless
319 it has a real, in-tree user. Mock-ups and tests based on ``netdevsim`` are
320 strongly encouraged when adding new APIs, but ``netdevsim`` in itself
321 is **not** considered a use case/user.
323 My company uses peer feedback in employee performance reviews. Can I ask netdev maintainers for feedback?
324 ---------------------------------------------------------------------------------------------------------
326 Yes, especially if you spend significant amount of time reviewing code
327 and go out of your way to improve shared infrastructure.
329 The feedback must be requested by you, the contributor, and will always
330 be shared with you (even if you request for it to be submitted to your