2 files changed, 17 insertions, 8 deletions

diff --git a/loader/unknown_function_handling.c b/loader/unknown_function_handling.c
index 16120c189..23e4e69f3 100644
--- a/loader/unknown_function_handling.c
+++ b/loader/unknown_function_handling.c
@@ -178,18 +178,17 @@ bool loader_check_icds_for_phys_dev_ext_address(struct loader_instance *inst, co
 
 bool loader_check_layer_list_for_phys_dev_ext_address(struct loader_instance *inst, const char *funcName) {
     struct loader_layer_properties *layer_prop_list = inst->expanded_activated_layer_list.list;
-    for (uint32_t layer = 0; layer < inst->expanded_activated_layer_list.count; ++layer) {
-        // If this layer supports the vk_layerGetPhysicalDeviceProcAddr, then call
-        // it and see if it returns a valid pointer for this function name.
+    for (uint32_t layer = 0; layer < inst->expanded_activated_layer_list.count; layer++) {
+        // Find the first layer in the call chain which supports vk_layerGetPhysicalDeviceProcAddr
+        // and call that, returning whether it found a valid pointer for this function name.
+        // We return if the topmost layer supports GPDPA since the layer should call down the chain for us.
         if (layer_prop_list[layer].interface_version > 1) {
             const struct loader_layer_functions *const functions = &(layer_prop_list[layer].functions);
-            if (NULL != functions->get_physical_device_proc_addr &&
-                NULL != functions->get_physical_device_proc_addr((VkInstance)inst->instance, funcName)) {
-                return true;
+            if (NULL != functions->get_physical_device_proc_addr) {
+                return NULL != functions->get_physical_device_proc_addr((VkInstance)inst->instance, funcName);
             }
         }
     }
-
     return false;
 }
 
@@ -327,4 +326,4 @@ void *loader_phys_dev_ext_gpa_term_no_check(struct loader_instance *inst, const
     }
 
     return NULL;
-}
\ No newline at end of file
+}
diff --git a/tests/framework/layer/test_layer.cpp b/tests/framework/layer/test_layer.cpp
index 5be8d8ddc..171703d1e 100644
--- a/tests/framework/layer/test_layer.cpp
+++ b/tests/framework/layer/test_layer.cpp
@@ -413,6 +413,12 @@ VKAPI_ATTR void VKAPI_CALL test_vkDestroyDevice(VkDevice device, const VkAllocat
         }
     }
 }
+// forward declarations needed for trampolines
+#if TEST_LAYER_EXPORT_GET_PHYSICAL_DEVICE_PROC_ADDR
+extern "C" {
+FRAMEWORK_EXPORT VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL vk_layerGetPhysicalDeviceProcAddr(VkInstance instance, const char* pName);
+}
+#endif
 
 // trampolines
 
@@ -435,6 +441,10 @@ VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL get_physical_device_func(VkInstance ins
             return to_vkVoidFunction(func.function);
         }
     }
+
+#if TEST_LAYER_EXPORT_GET_PHYSICAL_DEVICE_PROC_ADDR
+    if (string_eq(pName, "vk_layerGetPhysicalDeviceProcAddr")) return to_vkVoidFunction(vk_layerGetPhysicalDeviceProcAddr);
+#endif
     return nullptr;
 }