Man pages matching name ioctl_userfaultfd in section 2:

ioctl_userfaultfd.2.en	debian 10 / manpages-dev
ioctl_userfaultfd.2.en	debian 11 / manpages-dev
ioctl_userfaultfd.2.fr	debian 11 / manpages-fr-dev
ioctl_userfaultfd.2.en	debian 12 / manpages-dev
ioctl_userfaultfd.2.fr	debian 12 / manpages-fr-dev
ioctl_userfaultfd.2.ru	debian 12 / manpages-ru-dev