It honestly surprises me that no one has done something very similar with lxc (linux containers). There was an article recently about starting X from a container so something quasi-similar could be done.
Posted Apr 14, 2011 17:56 UTC (Thu) by trasz (guest, #45786)
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With lxc, you wouldn't solve the problems Qubes aims to fix (attack surface between userland and the kernel is simply too big; the whole protection would become useless with every exploitable security hole in kernel, which in Linux seems to happen every two months or so - and that's not including problems related to X11), and the overhead - administration overhead in particular - would be close.