Only deduplicate driver manifests

Code which was originally meant to deduplicate drivers that moved from the old
registry HKEY_LOCAL_MACHINE/SOFTWARE/Khronos/Vulkan/Drivers to PnP locations
was incorrectly applied to layers as well. The issue is that multiple layers
can share the same json file name but not actually contain the same manifest.
Worse, the first layer found would be assumed to be correct, even the file had
been deleted from the file system.

2 files changed, 45 insertions, 2 deletions

diff --git a/loader/loader_windows.c b/loader/loader_windows.c
index 4015acbb8..068e21147 100644
--- a/loader/loader_windows.c
+++ b/loader/loader_windows.c
@@ -525,8 +525,8 @@ VkResult windows_get_registry_files(const struct loader_instance *inst, char *lo
                                 foundDuplicate = true;
                             }
                         }
-
-                        if (foundDuplicate == false) {
+                        // Only skip if we are adding a driver and a duplicate was found
+                        if (!is_driver || (is_driver && foundDuplicate == false)) {
                             // Add the new entry to the list.
                             (void)snprintf(*reg_data + strlen(*reg_data), name_size + 2, "%c%s", PATH_SEPARATOR, name);
                             found = true;
diff --git a/tests/loader_regression_tests.cpp b/tests/loader_regression_tests.cpp
index 4bf72eb1f..7390596bd 100644
--- a/tests/loader_regression_tests.cpp
+++ b/tests/loader_regression_tests.cpp
@@ -3527,4 +3527,47 @@ TEST(AppPackageDriverDiscovery, AppPackageTest) {
     InstWrapper inst{env.vulkan_functions};
     inst.CheckCreate();
 }
+
+// Make sure that stale layer manifests (path to nonexistant file) which have the same name as real manifests don't cause the real
+// manifests to be skipped. Stale registry entries happen when a registry is written on layer/driver installation but not cleaned up
+// when the corresponding manifest is removed from the file system.
+TEST(DuplicateRegistryEntries, Layers) {
+    FrameworkEnvironment env{};
+    env.add_icd(TestICDDetails(ManifestICD{}.set_lib_path(TEST_ICD_PATH_VERSION_2)));
+
+    auto null_path = env.get_folder(ManifestLocation::null).location() / "test_layer.json";
+
+    env.platform_shim->add_manifest(ManifestCategory::explicit_layer, null_path.str());
+
+    const char* layer_name = "TestLayer";
+    env.add_explicit_layer(
+        ManifestLayer{}.add_layer(
+            ManifestLayer::LayerDescription{}.set_name(layer_name).set_lib_path(TEST_LAYER_PATH_EXPORT_VERSION_2)),
+        "test_layer.json");
+
+    InstWrapper inst{env.vulkan_functions};
+    inst.create_info.add_layer(layer_name);
+    inst.CheckCreate();
+}
+
+// Check that the de-duplication of drivers found in both PnP and generic Khronos/Vulkan/Drivers doesn't result in the same thing
+// being added twice
+TEST(DuplicateRegistryEntries, Drivers) {
+    FrameworkEnvironment env{};
+    auto null_path = env.get_folder(ManifestLocation::null).location() / "test_icd_0.json";
+    env.platform_shim->add_manifest(ManifestCategory::icd, null_path.str());
+
+    env.add_icd(TestICDDetails{TEST_ICD_PATH_VERSION_2_EXPORT_ICD_GPDPA}.set_discovery_type(ManifestDiscoveryType::none));
+    auto& driver = env.get_test_icd();
+    driver.physical_devices.emplace_back("physical_device_0");
+    driver.adapterLUID = _LUID{10, 1000};
+    env.platform_shim->add_d3dkmt_adapter(D3DKMT_Adapter{0, _LUID{10, 1000}}.add_driver_manifest_path(env.get_icd_manifest_path()));
+
+    InstWrapper inst{env.vulkan_functions};
+    FillDebugUtilsCreateDetails(inst.create_info, env.debug_log);
+    inst.CheckCreate();
+    ASSERT_TRUE(env.debug_log.find(
+        std::string("Skipping adding of json file \"") + null_path.str() +
+        "\" from registry \"HKEY_LOCAL_MACHINE\\SOFTWARE\\Khronos\\Vulkan\\Drivers\" to the list due to duplication"));
+}
 #endif