On Friday 2025-09-19 00:25, Cong Wang wrote:
>This patch series introduces multikernel architecture support, enabling >multiple independent kernel instances to coexist and communicate on a >single physical machine. > >Each kernel instance can run on dedicated CPU >cores while sharing the underlying hardware resources. I initially read it in such a way that that kernels run without supervisor, and thus necessarily cooperatively, on a system. But then I looked at <https://multikernel.io/assets/images/comparison-architecture-diagrams.svg>, saw that there is a kernel on top of a kernel, to which my reactive thought was: "well, that has been done before", e.g. User Mode Linux. While UML does not technically talk to hardware directly, continuing the thought "what's stopping a willing developer from giving /dev/mem to the subordinate kernel". On second thought, a hypervisor is just some kind of "miniature kernel" too (if generalizing very hard).
