You usually hope that TTD points to the culprit in such situations. But once I encountered single-byte corruption that didn't make any sense in TTD trace, there was good value at write and next read was garbage. I never discovered whether that was CPU bug, corruption by GPU shaders, stray kernel writes, or whatever.(I think it's unlikely that CPU bug would manifest with both native and TTD-instrumented runs. Corrupted byte was inside heap allocated memory so it shouldn't be in GPU pagetables at all. Kernel writes wouldn't appear in TTD trace, so really I think that was most likely issue, but how to debug that...)