Comment 8 for bug 686692

I think I see the issue now. When xen sets up the p2m tree, it does a loop from 0 to max_pfn-1, incrementing by the number of p2m mappings in the leaf. If max_pfn is a multiple of 4M this works out. But if not, we need an additional leaf being initialized (which is only partially used).

I need to think about how to make this work best. Maybe the end_pfn needs to be rounded up to the next multiple of P2M_PER_PAGE. And the next question would be how many places need to be touched as there is at least another place which sets up the corresponding pfn to mfn mapping...