func: int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size)
  
  {
  
          return kvm_dirty_pages_log_change(phys_addr, size,
  
                                            KVM_MEM_LOG_DIRTY_PAGES,
  
                                            KVM_MEM_LOG_DIRTY_PAGES);
  
  }
  