Fix VMM tests

cuda_core/pyproject.toml

@@ -51,7 +51,8 @@ cu12 = ["cuda-bindings[all]==12.*"]
 cu13 = ["cuda-bindings[all]==13.*"]
 
 [dependency-groups]
-test = ["cython>=3.2,<3.3", "setuptools", "pytest>=6.2.4"]
+# use cffi for VMM tests on Windows
+test = ["cython>=3.2,<3.3", "setuptools", "pytest>=6.2.4", "cffi; platform_system == \"Windows\""]
 test-cu12 = ["cuda-core[test]", "cupy-cuda12x; python_version < '3.14'", "cuda-toolkit[cudart]==12.*"]  # runtime headers needed by CuPy
 test-cu13 = ["cuda-core[test]", "cupy-cuda13x; python_version < '3.14'", "cuda-toolkit[cudart]==13.*"]  # runtime headers needed by CuPy
 # free threaded build, cupy doesn't support free-threaded builds yet, so avoid installing it for now

cuda_core/tests/test_memory.py

@@ -2,8 +2,8 @@
 # SPDX-License-Identifier: Apache-2.0
 
 import ctypes
+import functools
 import sys
-from ctypes import wintypes
 
 try:
     from cuda.bindings import driver
@@ -314,30 +314,65 @@ def test_device_memory_resource_initialization(mempool_device, use_device_object
     buffer.close()
 
 
-def get_handle_type():
-    def get_sa():
-        class SECURITY_ATTRIBUTES(ctypes.Structure):
-            _fields_ = [
-                ("nLength", wintypes.DWORD),
-                ("lpSecurityDescriptor", wintypes.LPVOID),
-                ("bInheritHandle", wintypes.BOOL),
-            ]
+@functools.cache
+def get_win32_object_attributes():
+    """If success, the returned pointer address to the OBJECT_ATTRIBUTES
+    object is valid within the test process lifetime. This helper function
+    is needed because OBJECT_ATTRIBUTES must be initialized by a macro
+    function, and the usual FFI/ctypes tricks do not work.
+    """
+    import tempfile
+
+    from cffi import FFI
+
+    prog = FFI()
+    prog.cdef("uintptr_t get_ptr_to_oa();")
+    source = r"""
+    #define _AMD64_
+    #include <ntdef.h>
+
+    static OBJECT_ATTRIBUTES objAttributes;
+
+    extern "C"
+    uintptr_t get_ptr_to_oa() {
+        static bool objAttributesConfigured = false;
+        if (!objAttributesConfigured) {
+            InitializeObjectAttributes(&objAttributes, NULL, 0, NULL, NULL);
+            objAttributesConfigured = true;
+        }
+        return reinterpret_cast<uintptr_t>(&objAttributes);
+    }
+    """
+    prog.set_source(
+        "mod_oa",
+        source,
+        source_extension=".cpp",
+        extra_compile_args=("/std:c++17",),
+    )
+    temp_dir = tempfile.mkdtemp()
+    prog.compile(tmpdir=temp_dir)
 
-        sa = SECURITY_ATTRIBUTES()
-        sa.nLength = ctypes.sizeof(sa)
-        sa.lpSecurityDescriptor = None
-        sa.bInheritHandle = False  # TODO: why?
+    sys.path.append(temp_dir)
+    from mod_oa.lib import get_ptr_to_oa
 
-        return sa
+    return get_ptr_to_oa()
 
+
+def get_handle_types():
     if IS_WINDOWS:
-        return (("win32", get_sa()), ("win32_kmt", None))
+        tests = [("win32_kmt", None)]
+        try:
+            ptr_to_oa = get_win32_object_attributes()
+            tests.append(("win32", ptr_to_oa))
+        except Exception:  # noqa: S110
+            pass
+        return tests
     else:
         return (("posix_fd", None),)
 
 
 @pytest.mark.parametrize("use_device_object", [True, False])
-@pytest.mark.parametrize("handle_type", get_handle_type())
+@pytest.mark.parametrize("handle_type", get_handle_types())
 def test_vmm_allocator_basic_allocation(use_device_object, handle_type):
     """Test basic VMM allocation functionality.
 
@@ -351,8 +386,8 @@ def test_vmm_allocator_basic_allocation(use_device_object, handle_type):
     if not device.properties.virtual_memory_management_supported:
         pytest.skip("Virtual memory management is not supported on this device")
 
-    handle_type, security_attribute = handle_type  # unpack
-    win32_handle_metadata = ctypes.addressof(security_attribute) if security_attribute else 0
+    handle_type, object_attributes = handle_type  # unpack
+    win32_handle_metadata = object_attributes if handle_type == "win32" else 0
     options = VirtualMemoryResourceOptions(
         handle_type=handle_type,
         win32_handle_metadata=win32_handle_metadata,
@@ -446,7 +481,7 @@ def test_vmm_allocator_policy_configuration():
     modified_buffer.close()
 
 
-@pytest.mark.parametrize("handle_type", get_handle_type())
+@pytest.mark.parametrize("handle_type", get_handle_types())
 def test_vmm_allocator_grow_allocation(handle_type):
     """Test VMM allocator's ability to grow existing allocations.
 
@@ -460,8 +495,8 @@ def test_vmm_allocator_grow_allocation(handle_type):
     if not device.properties.virtual_memory_management_supported:
         pytest.skip("Virtual memory management is not supported on this device")
 
-    handle_type, security_attribute = handle_type  # unpack
-    win32_handle_metadata = ctypes.addressof(security_attribute) if security_attribute else 0
+    handle_type, object_attributes = handle_type  # unpack
+    win32_handle_metadata = object_attributes if handle_type == "win32" else 0
     options = VirtualMemoryResourceOptions(
         handle_type=handle_type,
         win32_handle_metadata=win32_handle_metadata,