My model is effectively:

public class Project
{
    [Key]
    public Guid ProjectId { get; set; }

    public Guid ClientId { get; set; }
    public virtual Client Client { get; set; }
}

public class Client
{
    [Key]
    public Guid ClientId { get; set; }

    public virtual ICollection<Project> Projects { get; set; } = new List<Project>();
}

Up until I changed to the EntityFrameworkCore, I could fetch Projects with their associated Clients:

DbContext.Projects.Include(p => p.Client);

Since upgrading, I'm getting the error:
Additional information: Self referencing loop detected with type 'Models.Project'. Path 'Client.Projects'.

This should be pretty straight-forward: give me the Projects and their Clients. I don't want the Clients' Projects - else then I could see the issue with the loop.

I've mentioned this here:
aspnet/Mvc#4160