[Bug]: DeepSeek-R1-AWQ gets stuck with all tokens rejected when MTP is enabled.

[sgsdxzy]

Your current environment

The output of `python collect_env.py`

🐛 Describe the bug

Run command:

vllm serve --enable-chunked-prefill --enable-prefix-caching -tp 8 cognitivecomputations/DeepSeek-R1-AWQ --dtype float16 --trust-remote-code --max-model-len 131072 --max-seq-len-to-capture 131072 --num-speculative-tokens 1

Symptom:
Upon receiving a request, only the first word (for example "Okay") is generated, then the generation is stuck and no new tokens are streamed.

As can see from the console log, number of accepted tokens remains 0 while number draft tokens increases.

After removing --num-speculative-tokens 1 vllm works fine.

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