Fix NotImplementedError

✅ Solution

The "NotImplementedError" in vllm often arises when a requested feature or optimization, like a specific attention mechanism or tensor layout (e.g., for Mamba's DS conv state), hasn't been fully implemented for all execution paths or configurations within vllm. To resolve this, either complete the implementation for the missing functionality, ensuring all conditional branches are handled, or restrict usage by raising a more informative error or disabling the feature when the unsupported condition is detected.