we shouldn't call signal.disconnect in __del__ because it can lead to
deadlocks in Django signal dispatch code
The Signal.connect, Signal.disconnect, and Signal._live_receivers
methods all share a threading.Lock():
22a60f8d0b/django/dispatch/dispatcher.py (L49)
It's possible for this to lead to a deadlock:
1. Have code that calls Signal._live_receivers and enter the critical
path inside the shared threading.Lock()
2. Python garbage collection occurs and finds one or more LDAPBackend
objects with no more references
3. This __del__ is called, which calls Signal.disconnect
4. Code in Signal._disconnect attempts to obtain the (already held)
threading.Lock
5. Python hangs forever while attempting to garbage collect
AWX provides a web-based user interface, REST API, and task engine built on top of Ansible. It is the upstream project for Tower, a commercial derivative of AWX.
To install AWX, please view the Install guide.
To learn more about using AWX, and Tower, view the Tower docs site.
The AWX Project Frequently Asked Questions can be found here.
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Contributing
- Refer to the Contributing guide to get started developing, testing, and building AWX.
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develbranch. - All contributors must use git commit --signoff for any commit to be merged, and agree that usage of --signoff constitutes agreement with the terms of DCO 1.1
- Take care to make sure no merge commits are in the submission, and use
git rebasevsgit mergefor this reason. - If submitting a large code change, it's a good idea to join the
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If you're experiencing a problem that you feel is a bug in AWX, or have ideas for how to improve AWX, we encourage you to open an issue, and share your feedback. But before opening a new issue, we ask that you please take a look at our Issues guide.
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