**Environment**
- Isaac Sim: 6.0.1 official image (nvcr.io/nvidia/isaac-sim:6.0.1)
- GPU: NVIDIA GeForce RTX 4090 (24 GB), single card (GPU 0) — host has 2× 4090 but the
container is assigned GPU 0 only - Driver: 595.84 (CUDA 13.2)
- CPU: Intel Xeon w7-2495X (24 cores / 48 threads); OS: Ubuntu host, Docker container
- Mode: headless standalone via a self-written script (run_standalone.py, launched with
./python.sh, physics 100 Hz). Loads a Nova Carter rig + Rivermark scene, drives an RTX
LiDAR + IMU, publishes ROS 2 topics for SLAM testing. NOT an official Isaac Sim script.
**Summary**
Isaac Sim crashes with a random SIGSEGV in libcarb.taskingplugin.so. Crash timing is
non-deterministic — from ~10 s after startup up to 30+ hours. 7 crashes recorded between
2026-07-23 and 2026-08-15. The crash always resolves to the same fiber-switch point
(make_fcontext), consistent with a use-after-free / double-free.
**Crash stack** (from carb.crashreporter-breakpad.plugin)
libgpu.foundation.plugin.so!std::map::operator[]()
libcarb.tasking.plugin.so!std::string::_M_dispose()
libcarb.tasking.plugin.so!std::string::resize()
libcarb.tasking.plugin.so!make_fcontext
terminating with exit code 139 (SIGSEGV)
**Crash history** (from /root/.nvidia-omniverse/logs/carb.crashreporter.log)
— dump sizes 620–740 KB, consistent with a single crash site:
| # | Time (UTC) | dumpSize | Upload |
|---|---|---|---|
| 1 | 2026-07-23 05:37 | 666 KB | Success |
| 2 | 2026-07-23 09:31 | — | succeeded |
| 3 | 2026-07-24 01:01 | 620 KB | Success |
| 4 | 2026-07-29 04:41 | 740 KB | FailedButRetry |
| 5 | 2026-08-07 13:00 | 708 KB | Success |
| 6 | 2026-08-15 01:51 | 659 KB | Success |
| 7 | 2026-08-15 02:15 | 644 KB | Success |
**Minidump crash IDs / upload UUIDs** (for lookup in the crash DB)
1f50340a-849c-48f0-3a810aa1-dfbc6c71 (upload: ae43eb0e-c6c5-4448-ac04-4d79303f5c7a)
8c21ee4e-50d5-41be-58064b85-9478c327 (upload: 0cc0f61b-b709-4890-9953-f88f9e90c38f)
3e247a34-978c-47d5-42a32dbe-c30fcd0c (upload: b9b03cf7-48b0-4ecc-a445-f97715a71e65)
74a23193-c215-4381-e148f889-f7dcedb8 (upload failed/retry)
e73f2081-c7aa-48a0-f373d5a8-34fbda9f (upload: cca2ae75-c6ed-4a7c-98d0-28633584eb8c)
50b5f999-39e1-403f-30c3f9b0-93aeff65
**Already ruled out**
- NOT caused by material/asset UsdToMdl errors or MotionBVH warnings (cosmetic / expected).
- NOT caused by multi-GPU / P2P (the container uses a single card, GPU 0).
**Related reports** (for reference only, not a root-cause claim)
Forum post 371957 (“Isaac Sim 5.1.0 crashes on startup … segfaulting in
librtx.scenedb.plugin.so”) has a stack that also contains
libcarb.tasking.plugin.so!make_fcontext, where NVIDIA confirmed the 5.1.0 crash was caused
by the 595.x driver branch. We note this only as a similar stack signature.
**Questions**
- Is this a known libcarb.tasking use-after-free in 6.0.1?
- Any fix or workaround to reduce crash frequency?