Ajuda com duas entidade do hibernate

@Entity
@Table(name = "perfil")
public class Perfil implements java.io.Serializable, GrantedAuthority {

	private static final long serialVersionUID = 1L;

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	@Column(name = "id_perfil")
	private Long id;
	
	@Column(name = "descricao")
	private String descricao;
	
	@ManyToMany(fetch=FetchType.EAGER)
	@JoinTable(name = "usuario_perfil", joinColumns = @JoinColumn(name = "id_perfil"), inverseJoinColumns = @JoinColumn(name = "id_usuario"))
	private List<Usuario> usuarios = new ArrayList<Usuario>();


	@Transient
	public String getAuthority() {
		return this.descricao;
	}

	@Transient
	public int compareTo(Object o) {
		return this.compareTo(o);
	}

	public Long getId() {
		return id;
	}

	public void setId(Long id) {
		this.id = id;
	}

	public String getDescricao() {
		return descricao;
	}

	public void setDescricao(String descricao) {
		this.descricao = descricao;
	}

	public List<Usuario> getUsuarios() {
		return usuarios;
	}

	public void setUsuarios(List<Usuario> usuarios) {
		this.usuarios = usuarios;
	}

@Entity
@Table(name="usuario")
public class Usuario implements java.io.Serializable, UserDetails {
	
	private static final long serialVersionUID = 1L;

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	@Column(name = "id_usuario")
	private Long id;
	
	@Column(name = "login")
	private String login;
	
	@Column(name = "senha")
	private String senha;

	private boolean ativo = true;

	@ManyToMany(fetch = FetchType.EAGER)
	@JoinTable(name = "usuario_perfil", joinColumns = @JoinColumn(name = "id_usuario"), inverseJoinColumns = @JoinColumn(name = "id_perfil"))
	private List<Perfil> perfis = new ArrayList<Perfil>();

	@Transient
	public Collection<GrantedAuthority> getAuthorities() {
		List<GrantedAuthority> lista = new ArrayList<GrantedAuthority>();
		for(Perfil perfil : getPerfis()) {
			lista.add(new GrantedAuthorityImpl(perfil.getAuthority()));
		}
		return lista;
	}

	@Transient
	public String getPassword() {
		return this.senha;
	}

	@Transient
	public String getUsername() {
		return this.login;
	}

	@Transient
	public boolean isAccountNonExpired() {
		return this.ativo;
	}

	@Transient
	public boolean isAccountNonLocked() {
		return this.ativo;
	}

	@Transient
	public boolean isCredentialsNonExpired() {
		return this.ativo;
	}

	@Transient
	public boolean isEnabled() {
		return this.ativo;
	}

	public Long getId() {
		return id;
	}

	public void setId(Long id) {
		this.id = id;
	}

	public boolean isAtivo() {
		return ativo;
	}

	public void setAtivo(boolean ativo) {
		this.ativo = ativo;
	}

	public List<Perfil> getPerfis() {
		return perfis;
	}

	public void setPerfis(List<Perfil> perfis) {
		this.perfis = perfis;
	}

}