Free Software programmer
This blog existed before my current employment, and obviously reflects my own opinions and not theirs.
This work is licensed under a Creative Commons Attribution 2.1 Australia License.
Fri, 31 Aug 2007
Someone sent me a very polite mail asking what KVM-lite is. My bad.
KVM currently requires either AMD-V (SVM) or Intel's VT (VMX) extensions on the chip: these are implemented in separate modules. So it should be possible to implement a "lite" backend which uses lguest-like techniques to boot a (paravirtualized) guest.
Why? To increase the coverage and reach of KVM: many low-end machines are still shipping without sufficient hardware support. Having a single "kvm" which can run across everything (at least, for Linux) makes a great deal of sense.
Critically, it's not that hard. KVM already has emulation for all the parts of the PC we want. Paravirtual drivers are coming, as is a hypercall interface. KVM lite only has 6 hypercalls, and three of those can probably be replaced by emulation. More hypercalls will come (page table updates and batching), but normal KVM will want those too.
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