# CUDA 错误：无效的同步对象 (cudaErrorInvalidSyncObject)

- **ID:** `cuda/cuda-error-invalid-sync-object`
- **领域:** cuda
- **类别:** runtime_error
- **错误码:** `cudaErrorInvalidSyncObject (806)`
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

向期望有效、已初始化对象的 API 传递了 CUDA 同步对象（例如 cudaExternalSemaphore 或 cudaEvent），但该对象已被销毁、从未创建或在不同的设备上下文中创建。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| CUDA 12.5 | active | — | — |
| CUDA 12.7 | active | — | — |
| NVIDIA Driver 560.35.03 | active | — | — |
| NVIDIA Driver 565.57.01 | active | — | — |
| PyTorch 2.6.0 | active | — | — |

## 解决方案

1. ```
   Verify that the sync object is created on the correct device context. For example, in CUDA C++: `cudaSetDevice(deviceId); cudaEvent_t event; cudaEventCreate(&event);` Ensure all subsequent uses of `event` are on the same device.
   ```
2. ```
   Check if the sync object has been destroyed before reuse. Implement a wrapper that tracks the object's lifetime: `if (event) { cudaEventDestroy(event); event = nullptr; }`
   ```
3. ```
   For external semaphores, ensure the import handle is valid and the driver supports the semaphore type. Use `cudaImportExternalSemaphore` with a properly initialized `cudaExternalSemaphoreHandleDesc`.
   ```

## 无效尝试

- **** — Synchronizing the device does not recreate or validate the sync object; it only waits for pending operations to complete. (70% 失败率)
- **** — The error is about an invalid object handle, not resource exhaustion; more streams do not fix a null or cross-context object. (85% 失败率)
