[Bug 1124384] Re: reload-configuration can confuse upstart

[James Hunt]

I believe the problem here is that -- in the case where a JobClass has
no running instances -- a reload is causing the original JobClass to be
destroyed. That eventually leads to Event->blockers to reach zero (as a
result of the JobClasses EventOperators being freed) causing the event
to be destroyed. That behaviour is correct inasmuch as events are being
destroyed when they should. What is not correct is that the reload
results in all this happening *before* the newly-loaded JobClass gets a
chance to increment Event->blockers to avoid the event being freed.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to upstart in Ubuntu.
https://bugs.launchpad.net/bugs/1124384

Title:
  reload-configuration can confuse upstart

Status in “cloud-init” package in Ubuntu:
  Confirmed
Status in “upstart” package in Ubuntu:
  Confirmed

Bug description:
  Under bug 1080841 we made cloud-init invoke 'initctl reload-
  configuration' after it wrote a upstart job.  This was necessary
  because inotify is not supported on all filesystems (overlayfs being
  the one of most current interst).

  This seems to be causing upstart some pain, and resulting in cloud-
  final (and 'rc') not being run.

  Easy user-data to reproduce the problem is:

  #cloud-config-archive
  - content: |
     #cloud-boothook
     #!/bin/sh
     touch /run/cloud-init-upstart-reload  # hack, see trunk commit 783
  - content: |
     #!/bin/sh
     echo "==== $(date -R): user-script run ===" | tee /run/user-script.log
  - content: |
     #upstart-job
     description "a test upstart job"
     start on stopped rc RUNLEVEL=[2345]
     console output
     task
     script
     echo "==== $(date -R): upstart job run ===" | tee /run/upstart-job.log
     end script

  You should (and do on quantal) end up with 2 files written to /run.

  I've verified that the same behavior is true on quantal.  If you
  change cloud-init to notify upstart about a job immediately after it
  writes it, then quantal's upstart gets confused also.

  Related bugs:
   * bug 1080841: should reload configuration if an upstart job is added
   * bug 1103881: cloud-final is never executed if upstart is upgraded during initialization of the image

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1124384/+subscriptions