Installation Linux Kernel Version In order to use the UPF element, you must use the 5.0.0-23-generic version of the Linux kernel. free5gc uses the gtp5g kernel module, which has been tested and compiled against that kernel version only. To determine the version of the Linux kernel you are using: $ uname -r 5.0.0-23-generic Golang Version As noted above, free5gc is built and tested with Go 1.14.4..