Instalation fails with SELinux disabled

I know Gitlab assumes a SELinux-enabled system, but those of us who are trying to install Gitlab CE inside a docker container actually have no choice.

Even though SELinux is enabled on the host, docker containers always "fell like" SELinux is disabled - actually it is enabled, but the container "can't ask, can't tell", because all SELinux commands behave as if SELinux is disabled.

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Resource_Management_and_Linux_Containers_Guide/sec-Secure_Containers_with_SELinux.html