Spring webflux @ModelAttribute annotated methods not working with kotlin suspend methods #30894

I am using spring webflux with spring boot 3.1.0 and 1.1.0 io.spring.dependency-management gradle plugin(spring webflux 6.0.9).
According to documentation, spring should call methods annotated with @ModelAttribute before any @RequestMapping, and it should support reactive types for web flux. This works fine for Mono and Flux return types, but it doesn't work with kotlin suspend functions.

@Controller
class ViewController {

    @GetMapping("/")
    suspend fun homePage() : String {
        return "index"
    }
    @ModelAttribute(name = "roles")
    suspend fun roleAttributeInitializer(model: Model) : List<String>{
        return ReactiveSecurityContextHolder.getContext().map { sec -> sec.authentication?.authorities?.map { it.authority } ?: emptyList() }.awaitSingle()
    }

    @ModelAttribute
    suspend fun roleAttributeInitializer2(model: Model){
        model.addAttribute("roles",ReactiveSecurityContextHolder.getContext().map { sec -> sec.authentication?.authorities?.map { it.authority } ?: emptyList() })
    }

}

In the example above, methods annotated with @ModelAttribute are invoked after the @GetMapping annotated method when I debug with breakpoints.
Also, the first suspend method,even though invoked after @GetMapping, still populates the model correctly because it doesn't cause NullPointerException when rendering the view. But the second suspend method,which is also invoked after the @GetMapping, doesn't populate the model and I am getting NullPointerException when rendering the view because roles is null.