[Bugfix] Declare SupportsEagle3 on KimiLinearForCausalLM (#52171)

Signed-off-by: Nick Iusiumbeli <nickuspro@gmail.com>

tests/models/kimi_k3/test_eagle3.py

@@ -10,6 +10,7 @@ from vllm.model_executor.models.interfaces import supports_eagle3
 from vllm.models.kimi_k3.nvidia import model as kimi_model
 from vllm.models.kimi_k3.nvidia.model import (
     KimiK3ForConditionalGeneration,
+    KimiLinearForCausalLM,
     KimiLinearModel,
 )
 
@@ -25,6 +26,14 @@ def test_kimi_k3_advertises_eagle3_support():
     assert supports_eagle3(KimiK3ForConditionalGeneration)
 
 
+def test_kimi_linear_advertises_eagle3_support():
+    # The text-only architecture serves the same inner KimiLinearModel, which
+    # already carries the EagleModelMixin tap machinery - only the interface
+    # declaration was missing, so EAGLE3-family speculative decoding (dspark)
+    # was rejected at startup with "Model does not support EAGLE3 interface".
+    assert supports_eagle3(KimiLinearForCausalLM)
+
+
 def test_kimi_k3_uses_shared_eagle3_layer_configuration():
     target = object.__new__(KimiK3ForConditionalGeneration)
     torch.nn.Module.__init__(target)

vllm/models/kimi_k3/nvidia/model.py

@@ -1477,7 +1477,7 @@ class KimiLinearModel(nn.Module, EagleModelMixin, SupportsQuant):
 
 
 class KimiLinearForCausalLM(
-    nn.Module, HasInnerState, SupportsPP, MixtureOfExperts, IsHybrid
+    nn.Module, HasInnerState, SupportsPP, MixtureOfExperts, IsHybrid, SupportsEagle3
 ):
     def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
         super().__init__()