Two Objects Not Namespaced by the Linux Kernel (2017)
> The current set of namespaces in the kernel are: mount, pid, uts, ipc, net, user, and cgroup.  [...] [Time is] not namespaced.  [...] The kernel keyring is another item not namespaced.I've always argued that "everything is a file" is an exaggeration.  These moments make the extent of that exaggeration clear.If everything truly was a file, the only thing you would need to namespace is the filesystem.  But in reality there are a lot of other kernel objects that are not files at all.