diff --git a/vllm/model_executor/layers/layernorm.py b/vllm/model_executor/layers/layernorm.py
index 766bc46ce..7b222f9c4 100644
--- a/vllm/model_executor/layers/layernorm.py
+++ b/vllm/model_executor/layers/layernorm.py
@@ -241,8 +241,12 @@ class RMSNorm(CustomOp):
     ) -> torch.Tensor | tuple[torch.Tensor, torch.Tensor]:
         """PyTorch-native implementation equivalent to forward()."""
         if residual is None:
+            # TODO(luka): address the weight=None passing issue more generally
             return ir.ops.rms_norm(
-                x, self.weight.data, self.variance_epsilon, self.variance_size_override
+                x,
+                self.weight.data if self.has_weight else None,
+                self.variance_epsilon,
+                self.variance_size_override,
             )
 
         return self.forward_static(