RoGetActivationFactoryDetour doesn't support reentrancy?

[riverar]

My app is creating an instance of XamlControlsResources which involves RoGetActivationFactory. In at least one scenario, this involves creating an instance of PropertyMetadata while fulfilling this request, which results in another call to RoGetActivationFactory. But because of the unique_lock usage in the Mdd hook, this results in an exception.

I don't have a repro for you at this time (hence this is a discussion, not a proper issue), but consider the following stack:

00 KERNELBASE!RaiseException
01 Microsoft_WindowsAppSDK!_CxxThrowException
02 Microsoft_WindowsAppSDK!std::_Throw_Cpp_error
03 Microsoft_WindowsAppSDK!std::_Throw_C_error
04 Microsoft_WindowsAppSDK!std::_Check_C_return
05 Microsoft_WindowsAppSDK!std::_Mutex_base::lock
06 Microsoft_WindowsAppSDK!std::unique_lock<std::mutex>::{ctor}
07 Microsoft_WindowsAppSDK!MddCore::WinRTModuleManager::GetThreadingType
08 Microsoft_WindowsAppSDK!MddCore::WinRT::GetThreadingModel
09 Microsoft_WindowsAppSDK!WinRTGetThreadingModel_PackageGraph
0a Microsoft_WindowsAppSDK!WinRTGetThreadingModel
0b Microsoft_WindowsAppSDK!GetActivationLocation
0c Microsoft_WindowsAppSDK!RoGetActivationFactoryDetour
0d Microsoft_UI_Xaml_Controls!winrt::impl::get_runtime_activation_factory_impl<0>
0e Microsoft_UI_Xaml_Controls!winrt::impl::factory_cache_entry<winrt::Microsoft::UI::Xaml::PropertyMetadata,winrt::Microsoft::UI::Xaml::IPropertyMetadataFactory>::call<<lambda_073aad94565dae974f0649b9221facfc> & __ptr64>
0f Microsoft_UI_Xaml_Controls!InitializeDependencyProperty
10 Microsoft_UI_Xaml_Controls!XamlControlsResourcesProperties::EnsureProperties
11 Microsoft_UI_Xaml_Controls!winrt_make_Microsoft_UI_Xaml_Controls_XamlControlsResources
12 Microsoft_UI_Xaml_Controls!winrt_get_activation_factory
13 Microsoft_UI_Xaml_Controls!WINRT_GetActivationFactory
14 Microsoft_UI_Xaml_Controls!DllGetActivationFactory
15 Microsoft_WindowsAppSDK!MddCore::WinRTInprocModule::GetActivationFactory
16 Microsoft_WindowsAppSDK!MddCore::WinRTPackage::GetActivationFactory
17 Microsoft_WindowsAppSDK!MddCore::WinRTModuleManager::GetActivationFactory
18 Microsoft_WindowsAppSDK!MddCore::WinRT::GetActivationFactory
19 Microsoft_WindowsAppSDK!WinRTGetActivationFactory_PackageGraph
1a Microsoft_WindowsAppSDK!WinRTGetActivationFactory
1b Microsoft_WindowsAppSDK!RoGetActivationFactoryDetour
1c my_app!windows::runtime::factory_cache::RoGetActivationFactory
...

cc: @DrusTheAxe

[DrusTheAxe]

Sounds like a similar problem I ran into when initially testing this in WinAppSDK. I have a hunch what the problem is but will need to take a closer look before guessing how easy/hard it'll be to fix.

Thanks for bringing this to our attention!

[DrusTheAxe]

Issue created to track the problem #1277