From d2539980b6fc8244c3887b02c8d8d68237c053c9 Mon Sep 17 00:00:00 2001
From: Jimmy Shong <69131491+Jiminator@users.noreply.github.com>
Date: Wed, 17 Jun 2026 22:11:27 -0700
Subject: [PATCH] [Fix] don't force hybrid-SWA when sliding_window is disabled
 (#28604)

---
 python/sglang/srt/configs/laguna.py       | 5 +----
 python/sglang/srt/configs/model_config.py | 7 +++++++
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/python/sglang/srt/configs/laguna.py b/python/sglang/srt/configs/laguna.py
index 5e172d98f..45f9ad8a2 100644
--- a/python/sglang/srt/configs/laguna.py
+++ b/python/sglang/srt/configs/laguna.py
@@ -137,10 +137,7 @@ class LagunaConfig(PretrainedConfig):
         self.layer_types = (
             list(layer_types)
             if layer_types
-            else [
-                "full_attention" if i % 4 == 0 else "sliding_attention"
-                for i in range(num_hidden_layers)
-            ]
+            else ["full_attention" for _ in range(num_hidden_layers)]
         )
         self.mlp_layer_types = (
             list(mlp_layer_types)
diff --git a/python/sglang/srt/configs/model_config.py b/python/sglang/srt/configs/model_config.py
index abc43d354..b51e1c3a5 100644
--- a/python/sglang/srt/configs/model_config.py
+++ b/python/sglang/srt/configs/model_config.py
@@ -1724,6 +1724,13 @@ def is_hybrid_swa_model(
         "LagunaForCausalLM",
     }
     if any(arch in hybrid_swa_archs for arch in model_architectures):
+        # Only treat Laguna as hybrid SWA when it actually has a sliding window.
+        if (
+            "LagunaForCausalLM" in model_architectures
+            and hf_text_config is not None
+            and not getattr(hf_text_config, "sliding_window", 0)
+        ):
+            return False
         return True
     # Also recognize models that explicitly opt-in via their HF text config,
     # so custom hybrid-SWA architectures don't need to be added to the allowlist.