About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / stable_kernel_rules.txt


Based on kernel version 4.9. Page generated on 2016-12-21 14:37 EST.

1	.. _stable_kernel_rules:
2	
3	Everything you ever wanted to know about Linux -stable releases
4	===============================================================
5	
6	Rules on what kind of patches are accepted, and which ones are not, into the
7	"-stable" tree:
8	
9	 - It must be obviously correct and tested.
10	 - It cannot be bigger than 100 lines, with context.
11	 - It must fix only one thing.
12	 - It must fix a real bug that bothers people (not a, "This could be a
13	   problem..." type thing).
14	 - It must fix a problem that causes a build error (but not for things
15	   marked CONFIG_BROKEN), an oops, a hang, data corruption, a real
16	   security issue, or some "oh, that's not good" issue.  In short, something
17	   critical.
18	 - Serious issues as reported by a user of a distribution kernel may also
19	   be considered if they fix a notable performance or interactivity issue.
20	   As these fixes are not as obvious and have a higher risk of a subtle
21	   regression they should only be submitted by a distribution kernel
22	   maintainer and include an addendum linking to a bugzilla entry if it
23	   exists and additional information on the user-visible impact.
24	 - New device IDs and quirks are also accepted.
25	 - No "theoretical race condition" issues, unless an explanation of how the
26	   race can be exploited is also provided.
27	 - It cannot contain any "trivial" fixes in it (spelling changes,
28	   whitespace cleanups, etc).
29	 - It must follow the
30	   :ref:`Documentation/SubmittingPatches <submittingpatches>`
31	   rules.
32	 - It or an equivalent fix must already exist in Linus' tree (upstream).
33	
34	
35	Procedure for submitting patches to the -stable tree
36	----------------------------------------------------
37	
38	 - If the patch covers files in net/ or drivers/net please follow netdev stable
39	   submission guidelines as described in
40	   Documentation/networking/netdev-FAQ.txt
41	 - Security patches should not be handled (solely) by the -stable review
42	   process but should follow the procedures in
43	   :ref:`Documentation/SecurityBugs <securitybugs>`.
44	
45	For all other submissions, choose one of the following procedures
46	-----------------------------------------------------------------
47	
48	.. _option_1:
49	
50	Option 1
51	********
52	
53	To have the patch automatically included in the stable tree, add the tag
54	
55	.. code-block:: none
56	
57	     Cc: stable@vger.kernel.org
58	
59	in the sign-off area. Once the patch is merged it will be applied to
60	the stable tree without anything else needing to be done by the author
61	or subsystem maintainer.
62	
63	.. _option_2:
64	
65	Option 2
66	********
67	
68	After the patch has been merged to Linus' tree, send an email to
69	stable@vger.kernel.org containing the subject of the patch, the commit ID,
70	why you think it should be applied, and what kernel version you wish it to
71	be applied to.
72	
73	.. _option_3:
74	
75	Option 3
76	********
77	
78	Send the patch, after verifying that it follows the above rules, to
79	stable@vger.kernel.org.  You must note the upstream commit ID in the
80	changelog of your submission, as well as the kernel version you wish
81	it to be applied to.
82	
83	:ref:`option_1` is **strongly** preferred, is the easiest and most common.
84	:ref:`option_2` and :ref:`option_3` are more useful if the patch isn't deemed
85	worthy at the time it is applied to a public git tree (for instance, because
86	it deserves more regression testing first).  :ref:`option_3` is especially
87	useful if the patch needs some special handling to apply to an older kernel
88	(e.g., if API's have changed in the meantime).
89	
90	Note that for :ref:`option_3`, if the patch deviates from the original
91	upstream patch (for example because it had to be backported) this must be very
92	clearly documented and justified in the patch description.
93	
94	The upstream commit ID must be specified with a separate line above the commit
95	text, like this:
96	
97	.. code-block:: none
98	
99	    commit <sha1> upstream.
100	
101	Additionally, some patches submitted via Option 1 may have additional patch
102	prerequisites which can be cherry-picked. This can be specified in the following
103	format in the sign-off area:
104	
105	.. code-block:: none
106	
107	     Cc: <stable@vger.kernel.org> # 3.3.x: a1f84a3: sched: Check for idle
108	     Cc: <stable@vger.kernel.org> # 3.3.x: 1b9508f: sched: Rate-limit newidle
109	     Cc: <stable@vger.kernel.org> # 3.3.x: fd21073: sched: Fix affinity logic
110	     Cc: <stable@vger.kernel.org> # 3.3.x
111	     Signed-off-by: Ingo Molnar <mingo@elte.hu>
112	
113	The tag sequence has the meaning of:
114	
115	.. code-block:: none
116	
117	     git cherry-pick a1f84a3
118	     git cherry-pick 1b9508f
119	     git cherry-pick fd21073
120	     git cherry-pick <this commit>
121	
122	Also, some patches may have kernel version prerequisites.  This can be
123	specified in the following format in the sign-off area:
124	
125	.. code-block:: none
126	
127	     Cc: <stable@vger.kernel.org> # 3.3.x-
128	
129	The tag has the meaning of:
130	
131	.. code-block:: none
132	
133	     git cherry-pick <this commit>
134	
135	For each "-stable" tree starting with the specified version.
136	
137	Following the submission:
138	
139	 - The sender will receive an ACK when the patch has been accepted into the
140	   queue, or a NAK if the patch is rejected.  This response might take a few
141	   days, according to the developer's schedules.
142	 - If accepted, the patch will be added to the -stable queue, for review by
143	   other developers and by the relevant subsystem maintainer.
144	
145	
146	Review cycle
147	------------
148	
149	 - When the -stable maintainers decide for a review cycle, the patches will be
150	   sent to the review committee, and the maintainer of the affected area of
151	   the patch (unless the submitter is the maintainer of the area) and CC: to
152	   the linux-kernel mailing list.
153	 - The review committee has 48 hours in which to ACK or NAK the patch.
154	 - If the patch is rejected by a member of the committee, or linux-kernel
155	   members object to the patch, bringing up issues that the maintainers and
156	   members did not realize, the patch will be dropped from the queue.
157	 - At the end of the review cycle, the ACKed patches will be added to the
158	   latest -stable release, and a new -stable release will happen.
159	 - Security patches will be accepted into the -stable tree directly from the
160	   security kernel team, and not go through the normal review cycle.
161	   Contact the kernel security team for more details on this procedure.
162	
163	Trees
164	-----
165	
166	 - The queues of patches, for both completed versions and in progress
167	   versions can be found at:
168	
169		http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git
170	
171	 - The finalized and tagged releases of all stable kernels can be found
172	   in separate branches per version at:
173	
174		http://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git
175	
176	
177	Review committee
178	----------------
179	
180	 - This is made up of a number of kernel developers who have volunteered for
181	   this task, and a few that haven't.
Hide Line Numbers


About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog