When in the kernel you don't really have access to most of the standard library so there's no real guarantee that "libsiphash" wouldn't need symbols defined els

When in the kernel you don't really have access to most of the standard library so there's no real guarantee that "libsiphash" wouldn't need symbols defined elsewhere. The kernel does allow for loadable modules but the point of some of these hashes is to replace calls to some md5 and sha equivalents inside the kernel itself. As a result, the symbols would need to be defined at compile time (so these functions need to be compiled in).