[XPU] Let Inkling use the Mamba extra_buffer strategy on XPU

python/sglang/srt/arg_groups/overrides.py

@@ -416,7 +416,12 @@ def supports_mamba_cache_extra_buffer(view: Any, hf_config: Any) -> bool:
     the configured linear-attention backend (pure read)."""
     from sglang.srt.configs.linear_attn_model_registry import get_linear_attn_spec
 
-    if get_platform().is_xpu:
+    # Inkling has no no_buffer path (inkling.py asserts enable_mamba_extra_buffer),
+    # so rejecting it on XPU makes the model unlaunchable there.
+    if get_platform().is_xpu and hf_config.architectures[0] not in (
+        "InklingForConditionalGeneration",
+        "InklingForConditionalGenerationMTP",
+    ):
         return False
     spec = get_linear_attn_spec(hf_config)
     if hf_config.architectures[0] in _MAMBA_EXTRA_BUFFER_ARCHS or (

test/registered/unit/server_args/test_mamba_extra_buffer_platform.py

@@ -3,6 +3,7 @@
 from unittest.mock import patch
 
 from sglang.srt.arg_groups.mamba_hook import validate_mamba_extra_buffer
+from sglang.srt.arg_groups.overrides import supports_mamba_cache_extra_buffer
 from sglang.srt.runtime_context import override_platform
 from sglang.test.ci.ci_register import register_cpu_ci
 from sglang.test.test_utils import CustomTestCase
@@ -63,5 +64,32 @@ def test_out_of_tree_validation_uses_platform_capability(
             _validate()
 
 
+def _supports(arch: str) -> bool:
+    return supports_mamba_cache_extra_buffer(
+        SimpleNamespace(linear_attn_backend="triton"),
+        SimpleNamespace(architectures=[arch]),
+    )
+
+
+class TestMambaExtraBufferXpuArchs(CustomTestCase):
+    def test_inkling_is_admitted_on_xpu(self):
+        """Inkling has no no_buffer path, so rejecting it on XPU fails every launch."""
+        with override_platform(is_xpu=True):
+            for arch in (
+                "InklingForConditionalGeneration",
+                "InklingForConditionalGenerationMTP",
+            ):
+                with self.subTest(arch=arch):
+                    self.assertTrue(_supports(arch))
+
+    def test_other_archs_stay_rejected_on_xpu(self):
+        for arch in ("KimiK3ForConditionalGeneration", "NemotronHForCausalLM"):
+            with self.subTest(arch=arch):
+                with override_platform(is_xpu=False):
+                    self.assertTrue(_supports(arch))
+                with override_platform(is_xpu=True):
+                    self.assertFalse(_supports(arch))
+
+
 if __name__ == "__main__":
     unittest.main()