Fixing a crash when exiting or re-entering play mode#6296
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Fixes UUM-135678
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AlexRibard,
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montplaisir
…it (UUM-143767) Sensor writes during inference could overflow the tensor buffer when observation size exceeded the model's expected input, silently corrupting the allocator's internal metadata and causing non-deterministic crashes on MemoryManager::TryDeallocateWithLabel when exiting Play mode. Adds a capacity guard to ObservationGenerator's sensor write loop and bounds capping to all ObservationWriter TensorProxy write paths. Includes 13 regression tests covering overflow scenarios for every write method. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This reverts commit c84cc41.
montplaisir
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Jun 16, 2026
montplaisir
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Jun 16, 2026
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Good with 2 small fixes to do.
…to bobd/fix_crash_exit_playmode
Fixing string in warning
montplaisir
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Jun 17, 2026
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Merge branch 'update-gitignore' into bobd/fix_crash_exit_playmode
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Fixes UUM-135678, UUM-143767, UUM-135675, UUM-140974
Fixes a series of crash that could occur following memory overflow.
Proposed change(s)
Add tensor buffer bounds checks to prevent allocator corruption on exit (UUM-143767)
Sensor writes during inference could overflow the tensor buffer when
observation size exceeded the model's expected input, silently corrupting
the allocator's internal metadata and causing non-deterministic crashes
on MemoryManager::TryDeallocateWithLabel when exiting Play mode.
Adds a capacity guard to ObservationGenerator's sensor write loop and
bounds capping to all ObservationWriter TensorProxy write paths. Includes
13 regression tests covering overflow scenarios for every write method.
Retested intensively enter-exit play mode cycle on all user provided project and could not get it to crash again while it was crashing almost all the times before. Also tested exiting the editor in play mode in all the affected project as this was another way to trigger some of the crashes
Useful links (Github issues, JIRA tickets, ML-Agents forum threads etc.)
https://jira.unity3d.com/browse/UUM-135678
https://jira.unity3d.com/browse/UUM-143767
https://jira.unity3d.com/browse/UUM-135675
https://jira.unity3d.com/browse/UUM-140974
Types of change(s)
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