Alyssa Rosenzweig f18492faa9 lima,panfrost: Do not ralloc contexts against the screen
ralloc is not thread-safe. While a given context can only be accessed from a
single thread at once, multiple contexts can be created against the same screen
at once. The ralloc allocations against the shared screens will race. Depending
on the result of the race, the same block of memory can be returned as the two
new contexts in two different threads, causing a use-after-free when the context
is freed later.

We free the context explicitly when it's destroyed anyway. If screens are
getting destroyed without the contexts getting destroyed first, that's a state
tracker bug, not a Panfrost one.

This matches what Iris does.

Fixes crash in test_integer_ops.int_math on Panfrost.

Fixes: 0fcf73bc2d ("panfrost: Move to use ralloc for some allocations")
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17234>
2022-06-27 21:21:00 +00:00
2022-01-19 15:17:17 +00:00

`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library
======================================================


Source
------

This repository lives at https://gitlab.freedesktop.org/mesa/mesa.
Other repositories are likely forks, and code found there is not supported.


Build & install
---------------

You can find more information in our documentation (`docs/install.rst
<https://mesa3d.org/install.html>`_), but the recommended way is to use
Meson (`docs/meson.rst <https://mesa3d.org/meson.html>`_):

.. code-block:: sh

  $ mkdir build
  $ cd build
  $ meson ..
  $ sudo ninja install


Support
-------

Many Mesa devs hang on IRC; if you're not sure which channel is
appropriate, you should ask your question on `OFTC's #dri-devel
<irc://irc.oftc.net/dri-devel>`_, someone will redirect you if
necessary.
Remember that not everyone is in the same timezone as you, so it might
take a while before someone qualified sees your question.
To figure out who you're talking to, or which nick to ping for your
question, check out `Who's Who on IRC
<https://dri.freedesktop.org/wiki/WhosWho/>`_.

The next best option is to ask your question in an email to the
mailing lists: `mesa-dev\@lists.freedesktop.org
<https://lists.freedesktop.org/mailman/listinfo/mesa-dev>`_


Bug reports
-----------

If you think something isn't working properly, please file a bug report
(`docs/bugs.rst <https://mesa3d.org/bugs.html>`_).


Contributing
------------

Contributions are welcome, and step-by-step instructions can be found in our
documentation (`docs/submittingpatches.rst
<https://mesa3d.org/submittingpatches.html>`_).

Note that Mesa uses gitlab for patches submission, review and discussions.
Description
No description provided
Readme 545 MiB
Languages
C 75.3%
C++ 18.2%
Python 2.7%
Assembly 1.5%
Rust 1.2%
Other 0.9%