Quick Fix: fix Qwen3-VL launch failure caused by MRotaryEmbedding arg (#10985)

python/sglang/srt/layers/rotary_embedding.py

@@ -1065,6 +1065,7 @@ class MRotaryEmbedding(RotaryEmbedding):
         positions: torch.Tensor,
         query: torch.Tensor,
         key: torch.Tensor,
+        fused_set_kv_buffer_arg: Optional[FusedSetKVBufferArg] = None,
     ) -> Tuple[torch.Tensor, torch.Tensor]:
         """PyTorch-native implementation equivalent to forward().
 
@@ -1075,6 +1076,9 @@ class MRotaryEmbedding(RotaryEmbedding):
             query: [num_tokens, num_heads * head_size]
             key: [num_tokens, num_kv_heads * head_size]
         """
+        assert (
+            fused_set_kv_buffer_arg is None
+        ), "save kv cache is not supported for MRotaryEmbedding."
         assert positions.ndim == 1 or positions.ndim == 2
 
         num_tokens = positions.shape[-1]