Fix Baichuan2-7B-Chat (#1987)

Author: firebook

vllm/model_executor/models/baichuan.py

@@ -366,12 +366,16 @@ def load_weights(self,
                 weight_loader(param, loaded_weight)
 
 
-class BaichuanForCausalLM(BaiChuanBaseForCausalLM):  # baichuan 13b
+class BaichuanForCausalLM(BaiChuanBaseForCausalLM
+                          ):  # baichuan 13b, baichuan2 13b, baichuan2 7b
 
     def __init__(self,
                  config,
                  linear_method: Optional[LinearMethodBase] = None):
-        super().__init__(config, "ALIBI", linear_method)
+        if config.hidden_size == 4096:  # baichuan2 7b
+            super().__init__(config, "ROPE", linear_method)
+        else:  # baichuan 13b, baichuan2 13b
+            super().__init__(config, "ALIBI", linear_method)
 
 
 class BaiChuanForCausalLM(BaiChuanBaseForCausalLM):  # baichuan 7b