/usr/share/man/man3/free_hugepage_region.3.gz is in libhugetlbfs-dev 2.19-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man3/get_hugepage_region.3.gz
/usr/share/man/man3/get_hugepage_region.3.gz