[diffusion] fix: fix hunyuanvideo and add 2-gpu ci test (#13720)

Co-authored-by: Mick <mickjagger19@icloud.com>

python/sglang/multimodal_gen/configs/pipeline_configs/hunyuan.py

@@ -15,7 +15,10 @@ from sglang.multimodal_gen.configs.models.encoders import (
     LlamaConfig,
 )
 from sglang.multimodal_gen.configs.models.vaes import HunyuanVAEConfig
-from sglang.multimodal_gen.configs.pipeline_configs import PipelineConfig
+from sglang.multimodal_gen.configs.pipeline_configs.base import (
+    ModelTaskType,
+    PipelineConfig,
+)
 
 PROMPT_TEMPLATE_ENCODE_VIDEO = (
     "<|start_header_id|>system<|end_header_id|>\n\nDescribe the video by detailing the following aspects: "
@@ -66,6 +69,8 @@ def clip_postprocess_text(outputs: BaseEncoderOutput, _text_inputs) -> torch.ten
 class HunyuanConfig(PipelineConfig):
     """Base configuration for HunYuan pipeline architecture."""
 
+    task_type: ModelTaskType = ModelTaskType.T2V
+
     # HunyuanConfig-specific parameters with defaults
     # DiT
     dit_config: DiTConfig = field(default_factory=HunyuanVideoConfig)

python/sglang/multimodal_gen/configs/sample/base.py

@@ -414,6 +414,8 @@ class SamplingParams:
         if user_params is None:
             return
 
+        subclass_defined_fields = set(type(self).__annotations__.keys())
+
         # Compare against current instance to avoid constructing a default instance
         default_params = SamplingParams()
 
@@ -430,7 +432,7 @@ class SamplingParams:
                 if field_name != "output_file_name"
                 else user_params.output_file_path is not None
             )
-            if is_user_modified:
+            if is_user_modified and field_name not in subclass_defined_fields:
                 if hasattr(self, field_name):
                     setattr(self, field_name, user_value)