Ensure explicit multidriver teardown during context destroy

source/loader/ze_loader.cpp

@@ -1,6 +1,6 @@
 /*
  *
- * Copyright (C) 2019-2025 Intel Corporation
+ * Copyright (C) 2019-2026 Intel Corporation
  *
  * SPDX-License-Identifier: MIT
  *
@@ -9,6 +9,7 @@
 
 #include "driver_discovery.h"
 #include <iostream>
+#include <set>
 
 #ifdef __linux__
 #include <unistd.h>
@@ -824,18 +825,36 @@ namespace loader
             }
         }
 
-        for( auto& drv : allDrivers )
-        {
+        // Collect all unique driver handles from allDrivers, zeDrivers, and zesDrivers
+        // to ensure we free each library exactly once, avoiding double-free issues
+        std::set<HMODULE> uniqueHandles;
+        for (const auto& drv : allDrivers) {
             if (drv.handle) {
-                auto free_result = FREE_DRIVER_LIBRARY( drv.handle );
-                auto failure = FREE_DRIVER_LIBRARY_FAILURE_CHECK(free_result);
-                if (debugTraceEnabled && failure) {
-                    GET_LIBRARY_ERROR(freeLibraryErrorValue);
-                    if (!freeLibraryErrorValue.empty()) {
-                        std::string errorMessage = "Free Library Failed for " + drv.name + " With ";
-                        debug_trace_message(errorMessage, freeLibraryErrorValue);
-                        freeLibraryErrorValue.clear();
-                    }
+                uniqueHandles.insert(drv.handle);
+            }
+        }
+        for (const auto& drv : zeDrivers) {
+            if (drv.handle) {
+                uniqueHandles.insert(drv.handle);
+            }
+        }
+        for (const auto& drv : zesDrivers) {
+            if (drv.handle) {
+                uniqueHandles.insert(drv.handle);
+            }
+        }
+
+        // Free each unique driver library exactly once
+        for (auto handle : uniqueHandles)
+        {
+            auto free_result = FREE_DRIVER_LIBRARY( handle );
+            auto failure = FREE_DRIVER_LIBRARY_FAILURE_CHECK(free_result);
+            if (debugTraceEnabled && failure) {
+                GET_LIBRARY_ERROR(freeLibraryErrorValue);
+                if (!freeLibraryErrorValue.empty()) {
+                    std::string errorMessage = "Free Library Failed With ";
+                    debug_trace_message(errorMessage, freeLibraryErrorValue);
+                    freeLibraryErrorValue.clear();
                 }
             }
         }

test/CMakeLists.txt

@@ -9,10 +9,13 @@ add_executable(
   loader_tracing_layer.cpp
 )
 
-# Only include driver_ordering_unit_tests for static builds or non-Windows platforms
-# as it requires internal loader symbols that are not exported in Windows DLLs
+# Only include driver_ordering_unit_tests and driver_teardown_unit_tests for static builds or non-Windows platforms
+# as they require internal loader symbols that are not exported in Windows DLLs
 if(BUILD_STATIC OR NOT WIN32)
-  target_sources(tests PRIVATE driver_ordering_unit_tests.cpp)
+  target_sources(tests PRIVATE
+    driver_ordering_unit_tests.cpp
+    driver_teardown_unit_tests.cpp
+  )
 endif()
 
 # For builds on non-Windows platforms, include init_driver_unit_tests
@@ -745,7 +748,28 @@ set_property(TEST driver_ordering_trim_function PROPERTY ENVIRONMENT "ZE_ENABLE_
 
 add_test(NAME driver_ordering_parse_driver_order COMMAND tests --gtest_filter=DriverOrderingHelperFunctionsTest.ParseDriverOrder_*)
 set_property(TEST driver_ordering_parse_driver_order PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+# Driver Teardown Unit Tests
+add_test(NAME driver_teardown_unit_tests COMMAND tests --gtest_filter=DriverTeardownUnitTest.*)
+set_property(TEST driver_teardown_unit_tests PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+
+# Individual Driver Teardown Unit Tests for better granular reporting
+add_test(NAME driver_teardown_basic_collection COMMAND tests --gtest_filter=DriverTeardownUnitTest.NoDrivers_*:DriverTeardownUnitTest.AllNullHandles_*:DriverTeardownUnitTest.SingleDriverInAllDrivers_*:DriverTeardownUnitTest.MultipleUniqueHandlesInAllDrivers_*)
+set_property(TEST driver_teardown_basic_collection PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+
+add_test(NAME driver_teardown_duplicate_handles COMMAND tests --gtest_filter=DriverTeardownUnitTest.SameHandleInAllThreeVectors_*:DriverTeardownUnitTest.MultipleDuplicateHandlesAcrossVectors_*:DriverTeardownUnitTest.SameHandleInZeAndZesOnly_*)
+set_property(TEST driver_teardown_duplicate_handles PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+
+add_test(NAME driver_teardown_handle_distribution COMMAND tests --gtest_filter=DriverTeardownUnitTest.OnlyZeDriversHaveHandles_*:DriverTeardownUnitTest.OnlyZesDriversHaveHandles_*:DriverTeardownUnitTest.DifferentHandlesInEachVector_*)
+set_property(TEST driver_teardown_handle_distribution PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+
+add_test(NAME driver_teardown_realistic_scenarios COMMAND tests --gtest_filter=DriverTeardownUnitTest.SingleDriverScenario_*:DriverTeardownUnitTest.MultipleDriversScenario_*:DriverTeardownUnitTest.PartialInitialization_*:DriverTeardownUnitTest.DifferentDriversInitializedInZeVsZes_*)
+set_property(TEST driver_teardown_realistic_scenarios PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
+
+add_test(NAME driver_teardown_edge_cases COMMAND tests --gtest_filter=DriverTeardownUnitTest.MixedNullAndValidHandles_*:DriverTeardownUnitTest.VectorSizeMismatch_*:DriverTeardownUnitTest.LargeNumberOfDrivers_*:DriverTeardownUnitTest.CustomDriverScenario_*)
+set_property(TEST driver_teardown_edge_cases PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
 
+add_test(NAME driver_teardown_driver_types COMMAND tests --gtest_filter=DriverTeardownUnitTest.MixedDriverTypes_*:DriverTeardownUnitTest.ComplexRealWorldScenario_*)
+set_property(TEST driver_teardown_driver_types PROPERTY ENVIRONMENT "ZE_ENABLE_LOADER_DEBUG_TRACE=1;ZE_ENABLE_NULL_DRIVER=1")
 # Init Driver Unit Tests
 add_test(NAME init_driver_unit_tests COMMAND tests --gtest_filter=InitDriverUnitTest.*)
 if (MSVC)