process: Subproject maintenance and forward progress

We try to tackle the problem of allowing forward progress when all
maintainers of a subproject become unresponsive at the project level.

This proposal addresses openbmc/technical-oversight-forum#20

Change-Id: I5804a73959701b063e89f2cf4100ffbd3c1bd73f
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/process/subproject-maintainership.md b/process/subproject-maintainership.md
new file mode 100644
index 0000000..a084b5b
--- /dev/null
+++ b/process/subproject-maintainership.md
@@ -0,0 +1,259 @@
+# Subproject Maintainership and Forward Progress
+
+## Process
+
+1. A complaint is raised to the TOF about lack of forward progress in a
+   subproject
+2. The TOF validates the complaint against the pre-conditions and definitions
+   described below
+   1. The complaint is valid if all the pre-conditions are met and the behavior
+      exceeds the limits outlined in the definitions above
+   2. The complaint is partially valid if the pre-conditions are met and but the
+      behaviour does not exceed the limits outlined in the definitions above
+   3. The complaint is invalid if the pre-conditions are not met
+3. If the complaint is valid the TOF notifies the current maintainers of the
+   impending addition of maintainers
+   1. The TOF identifies the set of candidate maintainers
+   2. If willing candidates exist, one or more are added as subproject
+      maintainers
+   3. Otherwise, the TOF members mentor the complainant on maintenance until
+      there is consensus they would be considered a candidate. The TOF then
+      introduces the complainant as a maintainer
+4. If the complaint is partially valid then the TOF must notify the maintainers
+   of the impending addition of maintainers in the event of continued
+   unresponsiveness
+5. If the complaint is invalid then no further action is taken
+
+## Problem Description
+
+OpenBMC is a Linux distribution specialised for Baseboard Management Controllers
+(BMCs). While it exploits existing open-source projects where possible, the
+OpenBMC community also maintains many integrated projects that are specific to
+its use-cases.
+
+By observation, BMC firmware encounters a lot of diversity in use-cases as well
+as board and platform design. The shape of the project's community reflects the
+fact that developing OpenBMC-based systems is most effectively done by the
+companies designing the platforms. Reverse-engineering efforts
+exist([1][],[2][]) but do not represent the typical path by which platform
+support enters the project. As a consequence the community tends to be dominated
+by people contributing to the project to support the needs of their employer,
+and are broadly motivated by platform-specific requirements rather than general
+capabilities. The motivation for contribution by those in the community tends to
+be extrinsic.
+
+[1]:
+  https://github.com/Keno/openbmc/commit/327da25efde4fc54b27586be3914159136f03784
+[2]: https://lore.kernel.org/lkml/7baebe77f0f8963e06d5ddeec6c737f5@rnplus.nl/
+
+A consequence of this latter point is that engagement in the community can vary
+greatly with time based on events beyond the control of contributors and
+maintainers, through changes of roles, organisational direction or other factors
+like completion of support for a given platform.
+
+Extrinsic motivation driving variation in engagement is at odds with the
+consistency required by maintainer roles for the many integrated projects owned
+by the OpenBMC community.
+
+---
+
+The [Technical Oversight Forum (TOF) contract][tof-contract] paints the TOF's
+role in the project with broad brush strokes:
+
+[tof-contract]: /tof/contract.md
+
+> The TOF handles the processes around accepting new features into OpenBMC,
+> creating new subprojects (git repositories), approving subproject maintainers,
+> handling and enforcement of subproject maintainer issues, and many other
+> technical leadership concerns related to OpenBMC.
+
+and:
+
+> Issues the TOF handle include:
+>
+> - Approval of new bitbake meta layers.
+> - Approval of new subprojects.
+> - Supervising subproject maintainers.
+> - Resolving subproject maintainer disputes.
+> - Guidance and oversight of the technical direction of OpenBMC.
+
+These broad brush strokes touch on the TOF's responsibilities towards
+maintenance but the subject receives no further treatment.
+
+---
+
+[TOF issue #20][tof-issue-20] motivates exploration of a mechanism for it to
+introduce maintainers to subprojects to ensure the community can make forward
+progress when the existing maintainers become unresponsive.
+
+[tof-issue-20]: https://github.com/openbmc/technical-oversight-forum/issues/20
+
+## Scope
+
+While all unresponsive maintainers are problematic maintainers to some extent,
+it's not true that all problematic maintainers are unresponsive maintainers.
+This discussion specifically considers defining a mechanism to allow forward
+progress at the subproject scope in the face of unresponsive maintainers. It
+does not consider the more general problem of problematic maintainers.
+
+## Considerations
+
+The social, technical and security impacts of the TOF changing a subproject's
+maintainers are considered in the context of the following principle:
+
+> [Many decisions and actions are reversible and do not need extensive
+> study.][bias-for-action]
+
+[bias-for-action]: https://www.aboutamazon.com/about-us/leadership-principles
+
+The principle is used to prompt the question "Are the consequences easily
+reversed?" for each of the concerns below.
+
+### Social
+
+The [maintainer-workflow][] document recognises the personal effort required to
+become a maintainer:
+
+[maintainer-workflow]: /maintainer-workflow.md
+
+> Repository maintainers ought to have the following traits as recognized by a
+> consensus of their peers:
+>
+> - responsible: have a continuing desire to ensure only high-quality code goes
+>   into the repo
+> - leadership: foster open-source aware practices such as [FOSS][]
+> - expertise: typically demonstrated by significant contributions to the code
+>   or code reviews
+
+[FOSS]: https://en.wikipedia.org/wiki/Free_and_open-source_software
+
+Further, the community of maintainers inside the project [isn't broad enough to
+accommodate the review load][ed-is-only-human]. While unresponsive maintainers
+can be frustrating for contributors and a concern for the project, the problem
+needs to be weighed against the risk of alienating those who have (previously)
+put in the effort to build the project to its current capabilities. Healing
+alienation is at best intensive if not a futile effort; it is hard to reverse.
+This suggests that the TOF stepping in to remove maintainership responsibilities
+from community members without their consent is likely counter-productive,
+[contrary to the initial proposal][initial-proposal].
+
+[ed-is-only-human]:
+  https://lore.kernel.org/all/CAH2-KxAsq8=+kYZHb9n_fxE80SuU29yT90Hb0k72bKfY8pnWEQ@mail.gmail.com/
+[initial-proposal]:
+  https://github.com/openbmc/technical-oversight-forum/issues/20#issuecomment-1272667701
+
+### Technical
+
+At least two technical concerns exist:
+
+1. Contributors promoted to maintainers may lack or have no way to learn the
+   nuances and context for the current state of the codebase in question. There
+   may be a period (or periods) of instability until these issues are resolved.
+
+2. An unresponsive maintainer's knowledge of the codebase may age to the point
+   that it no-longer applies in the event that they attempt to return to the
+   subproject
+
+By the bias-for-action thought framework, (1) shouldn't be much of a concern in
+practice - it should be feasible to revert changes if necessary. This same
+approach applies in the case of (2) so long as the work is done in good faith.
+The process does need to consider the scenario where changes are not made in
+good faith.
+
+### Security
+
+Security concerns cut both ways. It's possible that:
+
+1. Contributors promoted to maintainers knowingly make changes that impact the
+   security posture of the project, or behave in a way that erodes or fails to
+   build the community's trust in their decision making.
+
+2. Not removing rights of an unresponsive maintainer from the subproject exposes
+   the project to a security hazard in the event that their account is
+   compromised.
+
+The first concern suggests that the contributors must have established trust
+relationships in the community before earning the responsibility of
+maintainership. It's hard to reverse a problem that isn't known to exist (though
+it may be possible to quickly revert the problematic code once its existence is
+known). Security problems can have an impact on the project's reputation; damage
+to reputation is also difficult to reverse, therefore the TOF needs to have
+confidence in any promotions.
+
+The second concern exists even for active maintainers and the process required
+to handle it might be the same: Removing rights until it's established that the
+compromise has been addressed. Unannounced activity from an otherwise
+unresponsive maintainer should itself be notable.
+
+### Synthesis of Considerations
+
+By the discussion above, a method for enabling forward progress should focus on
+putting guard-rails in place for the TOF to safely on-board new maintainers to a
+subproject. This is in contrast to not concerning itself too much with
+unresponsive maintainers, beyond recognising that they have met some bar of
+unresponsiveness in order to trigger the on-boarding process for new
+maintainers.
+
+## Defining and Determining Unresponsiveness
+
+Defining unresponsiveness sets expectations for both contributors and
+maintainers. Contributors can expect to have their work reviewed inside this
+period, and maintainers should endeavour to not let patches lapse.
+Responsiveness is a social contract.
+
+A tension exists between contributors needing feedback to maintain momentum
+against maintainers' available time both inside and outside the project.
+Maintainers are people: Life happens. Sometimes it is possible to communicate
+expected absences or hand over responsibilities, other times that may not
+happen. It's likely that unresponsiveness requires a fair margin in favour of
+maintainers, and that more than one instance should be needed before triggering
+the ability for the TOF to on-board new maintainers. Further, as it is a social
+contract it should be a socially-driven process: Inspection of the state of
+affairs in a subproject should only be performed if there are complaints about
+it, rather than using automation to detect the conditions.
+
+Unresponsiveness can appear at multiple scopes:
+
+1. Patch scope: Maintainers may ignore a given patch while attending to others
+2. Subproject scope: Maintainers may ignore a given repository while attending
+   to others
+3. Project scope: Maintainers may cease involvement in the project entirely
+
+Unresponsiveness at the patch scope would suggest a failure by the contributor
+and the maintainer to build consensus. It is already the role of the TOF to
+mediate these cases; this proposal considers such problems as out of scope.
+
+Unresponsiveness at the subproject scope but not the project scope suggests its
+at least possible to discuss on-boarding new maintainers to affected
+subprojects. Where possible, this is the preferred route to enabling forward
+progress. Failure of this process is again a failure of consensus, and is
+handled using existing mechanisms.
+
+The proposal concentrates on unresponsiveness at the project scope: Without
+regard to reason it is not possible to hold discussion with the maintainers in
+question.
+
+Lack of activity in a subproject is not evidence of lack of responsiveness. A
+pre-condition must be that unmerged contributions exist and remain unaddressed
+for the defined period.
+
+Further, multiple instances of unresponsiveness should be measured serially.
+Unresponsiveness is a property of behaviour in time: while the number of
+unaddressed contributions increases the impact and may increase frustrations,
+for any one period of unresponsiveness there is only one instance of the
+behaviour.
+
+Unresponsiveness also needs to be measured in terms of the set of maintainers.
+If any maintainer of a subproject is responsive in the project it's possible to
+make forward progress or to consider unaddressed contributions in terms of
+failed consensus. Therefore it is a pre-condition that all maintainers of a
+subproject are unresponsive at the project scope before the TOF may on-board new
+maintainers to enable forward progress.
+
+The following values apply when the pre-conditions are met:
+
+1. Maintainers are considered unresponsive after failing to address
+   contributions for a minimum period of 1 month.
+2. The TOF may on-board new maintainers to the subproject after 3 notifications
+   of unresponsiveness have been issued to the subproject's maintainers in a 12
+   month period.