c9674ad58b
k_thread_priority_set() on a pended thread wasn't re-inserting into the
waitq, causing the incorrect thread to run based on priority. When using
the scalable waitq config, this can also break assumptions of the tree
and leave the owner of a waitq still being in the waitq tree, cycles in
the tree, or a crash.
Remove and re-add a thread to a waitq to ensure the waitq remains in
order and the tree's assumptions are not violated.
To illustrate the issue, consider 4 threads in decreasing priority
order: A, B, C, and D along with two mutexes, m0 and m1. This is
implemented in the new complex_inversion mutex_api test.
1. D locks m1
2. C locks m0
3. C pends on m1
4. B pends on m1
5. A pends on m0, boosts C's priority, now tree on m1 is not sorted
6. D unlocks m1, left-most thread on tree is B. When removing B from
tree it cannot be found because it searches to the right of C due to
C's boosted priority when the node is actually on the left. rb_remove
silently fails.
7. B unlocks m1, left-most thread on tree is still B and it tries to
unpend itself, resulting in a NULL pointer dereference on
B->base.pended_on.
Signed-off-by: Josh DeWitt <josh.dewitt@garmin.com>
(cherry picked from commit c05cfbf15e)
.. raw:: html
<a href="https://www.zephyrproject.org">
<p align="center">
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<a href="https://scorecard.dev/viewer/?uri=github.com/zephyrproject-rtos/zephyr"><img src="https://api.securityscorecards.dev/projects/github.com/zephyrproject-rtos/zephyr/badge"></a>
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The Zephyr Project is a scalable real-time operating system (RTOS) supporting
multiple hardware architectures, optimized for resource constrained devices,
and built with security in mind.
The Zephyr OS is based on a small-footprint kernel designed for use on
resource-constrained systems: from simple embedded environmental sensors and
LED wearables to sophisticated smart watches and IoT wireless gateways.
The Zephyr kernel supports multiple architectures, including ARM (Cortex-A,
Cortex-R, Cortex-M), Intel x86, ARC, Nios II, Tensilica Xtensa, and RISC-V,
SPARC, MIPS, and a large number of `supported boards`_.
.. below included in doc/introduction/introduction.rst
Getting Started
***************
Welcome to Zephyr! See the `Introduction to Zephyr`_ for a high-level overview,
and the documentation's `Getting Started Guide`_ to start developing.
.. start_include_here
Community Support
*****************
Community support is provided via mailing lists and Discord; see the Resources
below for details.
.. _project-resources:
Resources
*********
Here's a quick summary of resources to help you find your way around:
Getting Started
---------------
| 📖 `Zephyr Documentation`_
| 🚀 `Getting Started Guide`_
| 🙋🏽 `Tips when asking for help`_
| 💻 `Code samples`_
Code and Development
--------------------
| 🌐 `Source Code Repository`_
| 📦 `Releases`_
| 🤝 `Contribution Guide`_
Community and Support
---------------------
| 💬 `Discord Server`_ for real-time community discussions
| 📧 `User mailing list (users@lists.zephyrproject.org)`_
| 📧 `Developer mailing list (devel@lists.zephyrproject.org)`_
| 📬 `Other project mailing lists`_
| 📚 `Project Wiki`_
Issue Tracking and Security
---------------------------
| 🐛 `GitHub Issues`_
| 🔒 `Security documentation`_
| 🛡️ `Security Advisories Repository`_
| ⚠️ Report security vulnerabilities at vulnerabilities@zephyrproject.org
Additional Resources
--------------------
| 🌐 `Zephyr Project Website`_
| 📺 `Zephyr Tech Talks`_
.. _Zephyr Project Website: https://www.zephyrproject.org
.. _Discord Server: https://chat.zephyrproject.org
.. _supported boards: https://docs.zephyrproject.org/latest/boards/index.html
.. _Zephyr Documentation: https://docs.zephyrproject.org
.. _Introduction to Zephyr: https://docs.zephyrproject.org/latest/introduction/index.html
.. _Getting Started Guide: https://docs.zephyrproject.org/latest/develop/getting_started/index.html
.. _Contribution Guide: https://docs.zephyrproject.org/latest/contribute/index.html
.. _Source Code Repository: https://github.com/zephyrproject-rtos/zephyr
.. _GitHub Issues: https://github.com/zephyrproject-rtos/zephyr/issues
.. _Releases: https://github.com/zephyrproject-rtos/zephyr/releases
.. _Project Wiki: https://github.com/zephyrproject-rtos/zephyr/wiki
.. _User mailing list (users@lists.zephyrproject.org): https://lists.zephyrproject.org/g/users
.. _Developer mailing list (devel@lists.zephyrproject.org): https://lists.zephyrproject.org/g/devel
.. _Other project mailing lists: https://lists.zephyrproject.org/g/main/subgroups
.. _Code samples: https://docs.zephyrproject.org/latest/samples/index.html
.. _Security documentation: https://docs.zephyrproject.org/latest/security/index.html
.. _Security Advisories Repository: https://github.com/zephyrproject-rtos/zephyr/security
.. _Tips when asking for help: https://docs.zephyrproject.org/latest/develop/getting_started/index.html#asking-for-help
.. _Zephyr Tech Talks: https://www.zephyrproject.org/tech-talks