new subclass

Signed-off-by: NickLucche <nlucches@redhat.com>

Author: NickLucche

vllm/v1/worker/gpu_model_runner.py

@@ -4574,7 +4574,9 @@ def get_kv_cache_spec(self) -> dict[str, KVCacheSpec]:
         kv_cache_spec: dict[str, KVCacheSpec] = {}
         attn_layers = get_layers_from_vllm_config(self.vllm_config, AttentionLayerBase)
         for layer_name, attn_module in attn_layers.items():
-            if (kv_tgt_layer := attn_module.kv_sharing_target_layer_name) is not None:
+            if isinstance(attn_module, Attention) and (
+                kv_tgt_layer := attn_module.kv_sharing_target_layer_name
+            ):
                 # The layer doesn't need its own KV cache and will use that of
                 # the target layer. We skip creating a KVCacheSpec for it, so
                 # that KV cache management logic will act as this layer does