создать файловый дескриптор для обработки ошибок страниц в пользовательском пространстве (create a file descriptor for handling page faults in user space)
Версии (Versions)
The userfaultfd() system call first appeared in Linux 4.3.
The support for hugetlbfs and shared memory areas and non-page-
fault events was added in Linux 4.11
