diff --git a/python/sglang/srt/mem_cache/allocation.py b/python/sglang/srt/mem_cache/allocation.py
index d87482278..9605c9e3b 100644
--- a/python/sglang/srt/mem_cache/allocation.py
+++ b/python/sglang/srt/mem_cache/allocation.py
@@ -352,7 +352,7 @@ def alloc_for_extend(
     else:
         # Paged allocation - build last_loc
         last_loc = [
-            (t[-1:] if len(t) > 0 else torch.tensor([-1], device=batch.device))
+            (t[-1:] if len(t) > 0 else torch.full((1,), -1, device=batch.device))
             for t in prefix_tensors
         ]
         out_cache_loc = alloc_paged_token_slots_extend(