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Based on kernel version 3.16. Page generated on 2014-08-06 21:40 EST.

1	
2	Information you need to know about netdev
3	-----------------------------------------
4	
5	Q: What is netdev?
6	
7	A: It is a mailing list for all network-related Linux stuff.  This includes
8	   anything found under net/  (i.e. core code like IPv6) and drivers/net
9	   (i.e. hardware specific drivers) in the Linux source tree.
10	
11	   Note that some subsystems (e.g. wireless drivers) which have a high volume
12	   of traffic have their own specific mailing lists.
13	
14	   The netdev list is managed (like many other Linux mailing lists) through
15	   VGER ( http://vger.kernel.org/ ) and archives can be found below:
16	
17		http://marc.info/?l=linux-netdev
18		http://www.spinics.net/lists/netdev/
19	
20	   Aside from subsystems like that mentioned above, all network-related Linux
21	   development (i.e. RFC, review, comments, etc.) takes place on netdev.
22	
23	Q: How do the changes posted to netdev make their way into Linux?
24	
25	A: There are always two trees (git repositories) in play.  Both are driven
26	   by David Miller, the main network maintainer.  There is the "net" tree,
27	   and the "net-next" tree.  As you can probably guess from the names, the
28	   net tree is for fixes to existing code already in the mainline tree from
29	   Linus, and net-next is where the new code goes for the future release.
30	   You can find the trees here:
31	
32		http://git.kernel.org/?p=linux/kernel/git/davem/net.git
33		http://git.kernel.org/?p=linux/kernel/git/davem/net-next.git
34	
35	Q: How often do changes from these trees make it to the mainline Linus tree?
36	
37	A: To understand this, you need to know a bit of background information
38	   on the cadence of Linux development.  Each new release starts off with
39	   a two week "merge window" where the main maintainers feed their new
40	   stuff to Linus for merging into the mainline tree.  After the two weeks,
41	   the merge window is closed, and it is called/tagged "-rc1".  No new
42	   features get mainlined after this -- only fixes to the rc1 content
43	   are expected.  After roughly a week of collecting fixes to the rc1
44	   content, rc2 is released.  This repeats on a roughly weekly basis
45	   until rc7 (typically; sometimes rc6 if things are quiet, or rc8 if
46	   things are in a state of churn), and a week after the last vX.Y-rcN
47	   was done, the official "vX.Y" is released.
48	
49	   Relating that to netdev:  At the beginning of the 2-week merge window,
50	   the net-next tree will be closed - no new changes/features.  The
51	   accumulated new content of the past ~10 weeks will be passed onto
52	   mainline/Linus via a pull request for vX.Y -- at the same time,
53	   the "net" tree will start accumulating fixes for this pulled content
54	   relating to vX.Y
55	
56	   An announcement indicating when net-next has been closed is usually
57	   sent to netdev, but knowing the above, you can predict that in advance.
58	
59	   IMPORTANT:  Do not send new net-next content to netdev during the
60	   period during which net-next tree is closed.
61	
62	   Shortly after the two weeks have passed (and vX.Y-rc1 is released), the
63	   tree for net-next reopens to collect content for the next (vX.Y+1) release.
64	
65	   If you aren't subscribed to netdev and/or are simply unsure if net-next
66	   has re-opened yet, simply check the net-next git repository link above for
67	   any new networking-related commits.
68	
69	   The "net" tree continues to collect fixes for the vX.Y content, and
70	   is fed back to Linus at regular (~weekly) intervals.  Meaning that the
71	   focus for "net" is on stabilization and bugfixes.
72	
73	   Finally, the vX.Y gets released, and the whole cycle starts over.
74	
75	Q: So where are we now in this cycle?
76	
77	A: Load the mainline (Linus) page here:
78	
79		http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git
80	
81	   and note the top of the "tags" section.  If it is rc1, it is early
82	   in the dev cycle.  If it was tagged rc7 a week ago, then a release
83	   is probably imminent.
84	
85	Q: How do I indicate which tree (net vs. net-next) my patch should be in?
86	
87	A: Firstly, think whether you have a bug fix or new "next-like" content.
88	   Then once decided, assuming that you use git, use the prefix flag, i.e.
89	
90		git format-patch --subject-prefix='PATCH net-next' start..finish
91	
92	   Use "net" instead of "net-next" (always lower case) in the above for
93	   bug-fix net content.  If you don't use git, then note the only magic in
94	   the above is just the subject text of the outgoing e-mail, and you can
95	   manually change it yourself with whatever MUA you are comfortable with.
96	
97	Q: I sent a patch and I'm wondering what happened to it.  How can I tell
98	   whether it got merged?
99	
100	A: Start by looking at the main patchworks queue for netdev:
101	
102		http://patchwork.ozlabs.org/project/netdev/list/
103	
104	   The "State" field will tell you exactly where things are at with
105	   your patch.
106	
107	Q: The above only says "Under Review".  How can I find out more?
108	
109	A: Generally speaking, the patches get triaged quickly (in less than 48h).
110	   So be patient.  Asking the maintainer for status updates on your
111	   patch is a good way to ensure your patch is ignored or pushed to
112	   the bottom of the priority list.
113	
114	Q: How can I tell what patches are queued up for backporting to the
115	   various stable releases?
116	
117	A: Normally Greg Kroah-Hartman collects stable commits himself, but
118	   for networking, Dave collects up patches he deems critical for the
119	   networking subsystem, and then hands them off to Greg.
120	
121	   There is a patchworks queue that you can see here:
122		http://patchwork.ozlabs.org/bundle/davem/stable/?state=*
123	
124	   It contains the patches which Dave has selected, but not yet handed
125	   off to Greg.  If Greg already has the patch, then it will be here:
126		http://git.kernel.org/cgit/linux/kernel/git/stable/stable-queue.git
127	
128	   A quick way to find whether the patch is in this stable-queue is
129	   to simply clone the repo, and then git grep the mainline commit ID, e.g.
130	
131		stable-queue$ git grep -l 284041ef21fdf2e
132		releases/3.0.84/ipv6-fix-possible-crashes-in-ip6_cork_release.patch
133		releases/3.4.51/ipv6-fix-possible-crashes-in-ip6_cork_release.patch
134		releases/3.9.8/ipv6-fix-possible-crashes-in-ip6_cork_release.patch
135		stable/stable-queue$
136	
137	Q: I see a network patch and I think it should be backported to stable.
138	   Should I request it via "stable@vger.kernel.org" like the references in
139	   the kernel's Documentation/stable_kernel_rules.txt file say?
140	
141	A: No, not for networking.  Check the stable queues as per above 1st to see
142	   if it is already queued.  If not, then send a mail to netdev, listing
143	   the upstream commit ID and why you think it should be a stable candidate.
144	
145	   Before you jump to go do the above, do note that the normal stable rules
146	   in Documentation/stable_kernel_rules.txt still apply.  So you need to
147	   explicitly indicate why it is a critical fix and exactly what users are
148	   impacted.  In addition, you need to convince yourself that you _really_
149	   think it has been overlooked, vs. having been considered and rejected.
150	
151	   Generally speaking, the longer it has had a chance to "soak" in mainline,
152	   the better the odds that it is an OK candidate for stable.  So scrambling
153	   to request a commit be added the day after it appears should be avoided.
154	
155	Q: I have created a network patch and I think it should be backported to
156	   stable.  Should I add a "Cc: stable@vger.kernel.org" like the references
157	   in the kernel's Documentation/ directory say?
158	
159	A: No.  See above answer.  In short, if you think it really belongs in
160	   stable, then ensure you write a decent commit log that describes who
161	   gets impacted by the bugfix and how it manifests itself, and when the
162	   bug was introduced.  If you do that properly, then the commit will
163	   get handled appropriately and most likely get put in the patchworks
164	   stable queue if it really warrants it.
165	
166	   If you think there is some valid information relating to it being in
167	   stable that does _not_ belong in the commit log, then use the three
168	   dash marker line as described in Documentation/SubmittingPatches to
169	   temporarily embed that information into the patch that you send.
170	
171	Q: Someone said that the comment style and coding convention is different
172	   for the networking content.  Is this true?
173	
174	A: Yes, in a largely trivial way.  Instead of this:
175	
176		/*
177		 * foobar blah blah blah
178		 * another line of text
179		 */
180	
181	   it is requested that you make it look like this:
182	
183		/* foobar blah blah blah
184		 * another line of text
185		 */
186	
187	Q: I am working in existing code that has the former comment style and not the
188	   latter.  Should I submit new code in the former style or the latter?
189	
190	A: Make it the latter style, so that eventually all code in the domain of
191	   netdev is of this format.
192	
193	Q: I found a bug that might have possible security implications or similar.
194	   Should I mail the main netdev maintainer off-list?
195	
196	A: No. The current netdev maintainer has consistently requested that people
197	   use the mailing lists and not reach out directly.  If you aren't OK with
198	   that, then perhaps consider mailing "security@kernel.org" or reading about
199	   http://oss-security.openwall.org/wiki/mailing-lists/distros
200	   as possible alternative mechanisms.
201	
202	Q: What level of testing is expected before I submit my change?
203	
204	A: If your changes are against net-next, the expectation is that you
205	   have tested by layering your changes on top of net-next.  Ideally you
206	   will have done run-time testing specific to your change, but at a
207	   minimum, your changes should survive an "allyesconfig" and an
208	   "allmodconfig" build without new warnings or failures.
209	
210	Q: Any other tips to help ensure my net/net-next patch gets OK'd?
211	
212	A: Attention to detail.  Re-read your own work as if you were the
213	   reviewer.  You can start with using checkpatch.pl, perhaps even
214	   with the "--strict" flag.  But do not be mindlessly robotic in
215	   doing so.  If your change is a bug-fix, make sure your commit log
216	   indicates the end-user visible symptom, the underlying reason as
217	   to why it happens, and then if necessary, explain why the fix proposed
218	   is the best way to get things done.   Don't mangle whitespace, and as
219	   is common, don't mis-indent function arguments that span multiple lines.
220	   If it is your first patch, mail it to yourself so you can test apply
221	   it to an unpatched tree to confirm infrastructure didn't mangle it.
222	
223	   Finally, go back and read Documentation/SubmittingPatches to be
224	   sure you are not repeating some common mistake documented there.
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