FIX: support language_model.backbone naming in NemotronH Nano VL quantization config (#39901)

Signed-off-by: <>
Co-authored-by: root <root@lyris0144.lyris.clusters.nvidia.com>

vllm/model_executor/models/nano_nemotron_vl.py

@@ -37,6 +37,7 @@ from vllm.model_executor.models.nemotron_h import NemotronHForCausalLM
 from vllm.model_executor.models.parakeet import ParakeetExtractor, ProjectedParakeet
 from vllm.model_executor.models.radio import RadioModel, calc_seq_lens
 from vllm.model_executor.models.utils import (
+    WeightsMapper,
     init_vllm_registered_model,
     maybe_prefix,
 )
@@ -903,6 +904,12 @@ class NemotronH_Nano_VL_V2(
     requires_sequential_video_encoding = True
     """Temporarily needed for dynamic res video w/ conv3d, doesn't support bs>1 yet"""
 
+    hf_to_vllm_mapper = WeightsMapper(
+        orig_to_new_prefix={
+            "language_model.backbone": "language_model.model",
+        },
+    )
+
     @classmethod
     def get_placeholder_str(cls, modality: str, i: int) -> str | None:
         if modality.startswith("image"):