/usr/share/man/man8/mkreiser4.8.gz is in reiser4progs 1.1.0-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man8/mkfs.reiser4.8.gz
/usr/share/man/man8/mkfs.reiser4.8.gz