Bug#506917: pbuilder does not work correctly with selinux if selinux-utils is not installed

[Alexander Block]

> Hmm no idea how to properly check for selinux enablement; perhaps we
>  can poke something in /proc or in /selinux?
>
>  Last resort, we could move to a grep /selinux in /proc/mounts.
/selinux is mounted with fs type 'selinuxfs', which I expect to be not 
available when selinux is disabled. Can't you try to mount it always and 
ignore if it fails?

And even if does not fail on a system without /selinux, would this be a 
problem?