Documentation/stable_kernel_rules.txt

   1 Everything you ever wanted to know about Linux -stable releases.
   2
   3 Rules on what kind of patches are accepted, and which ones are not, into the
   4 "-stable" tree:
   5
   6  - It must be obviously correct and tested.
   7  - It cannot be bigger than 100 lines, with context.
   8  - It must fix only one thing.
   9  - It must fix a real bug that bothers people (not a, "This could be a
  10    problem..." type thing).
  11  - It must fix a problem that causes a build error (but not for things
  12    marked CONFIG_BROKEN), an oops, a hang, data corruption, a real
  13    security issue, or some "oh, that's not good" issue.  In short, something
  14    critical.
  15  - Serious issues as reported by a user of a distribution kernel may also
  16    be considered if they fix a notable performance or interactivity issue.
  17    As these fixes are not as obvious and have a higher risk of a subtle
  18    regression they should only be submitted by a distribution kernel
  19    maintainer and include an addendum linking to a bugzilla entry if it
  20    exists and additional information on the user-visible impact.
  21  - New device IDs and quirks are also accepted.
  22  - No "theoretical race condition" issues, unless an explanation of how the
  23    race can be exploited is also provided.
  24  - It cannot contain any "trivial" fixes in it (spelling changes,
  25    whitespace cleanups, etc).
  26  - It must follow the Documentation/SubmittingPatches rules.
  27  - It or an equivalent fix must already exist in Linus' tree (upstream).
  28
  29
  30 Procedure for submitting patches to the -stable tree:
  31
  32  - If the patch covers files in net/ or drivers/net please follow netdev stable
  33    submission guidelines as described in
  34    Documentation/networking/netdev-FAQ.txt
  35  - Security patches should not be handled (solely) by the -stable review
  36    process but should follow the procedures in Documentation/SecurityBugs.
  37
  38 For all other submissions, choose one of the following procedures:
  39
  40    --- Option 1 ---
  41
  42    To have the patch automatically included in the stable tree, add the tag
  43      Cc: stable@vger.kernel.org
  44    in the sign-off area. Once the patch is merged it will be applied to
  45    the stable tree without anything else needing to be done by the author
  46    or subsystem maintainer.
  47
  48    --- Option 2 ---
  49
  50    After the patch has been merged to Linus' tree, send an email to
  51    stable@vger.kernel.org containing the subject of the patch, the commit ID,
  52    why you think it should be applied, and what kernel version you wish it to
  53    be applied to.
  54
  55    --- Option 3 ---
  56
  57    Send the patch, after verifying that it follows the above rules, to
  58    stable@vger.kernel.org.  You must note the upstream commit ID in the
  59    changelog of your submission, as well as the kernel version you wish
  60    it to be applied to.
  61
  62 Option 1 is *strongly* preferred, is the easiest and most common.  Options 2 and
  63 3 are more useful if the patch isn't deemed worthy at the time it is applied to
  64 a public git tree (for instance, because it deserves more regression testing
  65 first).  Option 3 is especially useful if the patch needs some special handling
  66 to apply to an older kernel (e.g., if API's have changed in the meantime).
  67
  68 Note that for Option 3, if the patch deviates from the original upstream patch
  69 (for example because it had to be backported) this must be very clearly
  70 documented and justified in the patch description.
  71
  72 The upstream commit ID must be specified with a separate line above the commit
  73 text, like this:
  74
  75     commit <sha1> upstream.
  76
  77 Additionally, some patches submitted via Option 1 may have additional patch
  78 prerequisites which can be cherry-picked. This can be specified in the following
  79 format in the sign-off area:
  80
  81      Cc: <stable@vger.kernel.org> # 3.3.x: a1f84a3: sched: Check for idle
  82      Cc: <stable@vger.kernel.org> # 3.3.x: 1b9508f: sched: Rate-limit newidle
  83      Cc: <stable@vger.kernel.org> # 3.3.x: fd21073: sched: Fix affinity logic
  84      Cc: <stable@vger.kernel.org> # 3.3.x
  85     Signed-off-by: Ingo Molnar <mingo@elte.hu>
  86
  87    The tag sequence has the meaning of:
  88      git cherry-pick a1f84a3
  89      git cherry-pick 1b9508f
  90      git cherry-pick fd21073
  91      git cherry-pick <this commit>
  92
  93 Also, some patches may have kernel version prerequisites.  This can be
  94 specified in the following format in the sign-off area:
  95
  96      Cc: <stable@vger.kernel.org> # 3.3.x-
  97
  98    The tag has the meaning of:
  99      git cherry-pick <this commit>
 100
 101    For each "-stable" tree starting with the specified version.
 102
 103 Following the submission:
 104
 105  - The sender will receive an ACK when the patch has been accepted into the
 106    queue, or a NAK if the patch is rejected.  This response might take a few
 107    days, according to the developer's schedules.
 108  - If accepted, the patch will be added to the -stable queue, for review by
 109    other developers and by the relevant subsystem maintainer.
 110
 111
 112 Review cycle:
 113
 114  - When the -stable maintainers decide for a review cycle, the patches will be
 115    sent to the review committee, and the maintainer of the affected area of
 116    the patch (unless the submitter is the maintainer of the area) and CC: to
 117    the linux-kernel mailing list.
 118  - The review committee has 48 hours in which to ACK or NAK the patch.
 119  - If the patch is rejected by a member of the committee, or linux-kernel
 120    members object to the patch, bringing up issues that the maintainers and
 121    members did not realize, the patch will be dropped from the queue.
 122  - At the end of the review cycle, the ACKed patches will be added to the
 123    latest -stable release, and a new -stable release will happen.
 124  - Security patches will be accepted into the -stable tree directly from the
 125    security kernel team, and not go through the normal review cycle.
 126    Contact the kernel security team for more details on this procedure.
 127
 128 Trees:
 129
 130  - The queues of patches, for both completed versions and in progress
 131    versions can be found at:
 132         http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git
 133  - The finalized and tagged releases of all stable kernels can be found
 134    in separate branches per version at:
 135         http://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git
 136
 137
 138 Review committee:
 139
 140  - This is made up of a number of kernel developers who have volunteered for
 141    this task, and a few that haven't.