diff --git a/flashinfer/compilation_context.py b/flashinfer/compilation_context.py
index c6072fb2a5..08ccabae7e 100644
--- a/flashinfer/compilation_context.py
+++ b/flashinfer/compilation_context.py
@@ -36,28 +36,20 @@ def _normalize_cuda_arch(major: int, minor: int) -> tuple[int, str]:
         tuple with the correct architecture suffix for nvcc.
 
         SM 9.x  -> 'a' suffix (e.g. compute_90a)
-        SM 12.x -> always normalized to SM 120 with 'f' suffix (e.g. compute_120f)
-                    when the installed CUDA toolchain supports it (CUDA >= 13.0),
-                    otherwise 'a'.  This covers both SM 12.0 and SM 12.1 (DGX Spark).
+        SM 12.x -> always normalized to SM 120 with 'f' suffix (e.g. compute_120f).
+        This covers both SM 12.0 and SM 12.1 (DGX Spark) when the installed CUDA toolchain supports it (CUDA >= 12.9).
         SM 10+  -> 'a' suffix (e.g. compute_100a)
         SM < 9  -> no suffix
         """
         if major == 9:
             return (major, str(minor) + "a")
         elif major == 12:
-            try:
-                from flashinfer.jit.cpp_ext import is_cuda_version_at_least
+            from flashinfer.jit.cpp_ext import is_cuda_version_at_least
 
-                if is_cuda_version_at_least("13.0"):
-                    return (major, "0f")
-            except (ImportError, RuntimeError, ValueError):
-                logger.debug(
-                    "Could not determine CUDA version; "
-                    "falling back to 'a' suffix for SM %d.%d",
-                    major,
-                    minor,
-                )
-            return (major, "0a")
+            if is_cuda_version_at_least("12.9"):
+                return (major, "0f")
+            else:
+                raise RuntimeError("SM 12.x requires CUDA >= 12.9")
         elif major >= 10:
             return (major, str(minor) + "a")
         return (major, str(minor))