How to make every page of a process in the page table present?

Hi all:
i compiled a static program using gcc on linux and run it under kvm. I
checked every page table entry of this process in guest memory and
found that some pages have been mapped and some ones are not. Is this
the feature of on-demand paging?
My question is whether there is a solution to make all the pte present
and mapped in the page table?
E.g. i fork a new process and load a new elf binary, how to make every
page mapped in the page table of this new process.

Thanks
-- 
Zhongshu