Alex & All: Here is a gap analysis for paravirt_ops, can you all comment? In summary we have 4 catagory of jobs: 1: CPU paravirt_ops including MMU & timer & interrupt 2: Xen hooks 3: irq chip paravirt_ops, xen irq chip or vSAPIC? 4: dma for driver domain

My understanding is that the effort is almost similar for each part, while all various alternatives such as pre-virtualization, binary patching (privify) or even unmodified Linux as dom0 only save part of #1 effort, which means less than 25% effort saving. Do we really want a temporary solution for 25%- effort saving? So I would suggest we go with paravirt_ops which is the Linux community direction to avoid resource fragmentation. The writeup is very draft and I am planning to spend more time in investigation, comments are welcome. thx, eddie