In the course of fixing XSA-378 fallout I ran into a number of
issues, the remaining parts of which this series is trying to deal
with. The majority of the changes is pretty much independent of
one another.

There was another rather basic issue to fight first (patch
was submitted separately as RFC): vPCI wasn't aware of hidden PCI
devices, hitting an ASSERT(). Obviously I couldn't afford not
having a functioning serial console.

Compared to v3 there is one new patch here, and the video mode
propagation one has been dropped for effectively having got
rejected. I realize that discussion on what exactly to include in
patch 3 has not settled yet; that patch is deliberately unchanged.
See individual patches for details.

1: PVH: improve Dom0 memory size calculation
2: PV: properly set shadow allocation for Dom0
3: PVH: permit more physdevop-s to be used by Dom0
4: HVM: also dump stacks from show_execution_state()
5: HVM: skip offline vCPU-s when dumping VMCBs/VMCSes
6: P2M: relax permissions of PVH Dom0's MMIO entries

Jan