Recent changes related to arm64 support in MSHV exposed
inconsistencies in the VM initialization and CVM boot paths.
The VM creation flow currently diverges across multiple scenarios,
including regular MSHV, CVM, and arm64, with each path performing
guest initialization steps in a different order.
Certain platform-specific requirements further constrain the ordering
of operations, such as the timing of address space creation,
IGVM loading, interrupt controller setup, and payload loading. For
CVM case address-space creation must be done after IGVM loading, and
PSP measurement. For Regular and arm64 this memory initialization
must be done early. For MSHV, vm.init() and sev_snp.init() are called in
different order which is run time and build time conditionally checked.
Additionally, while the KVM initialization path differs slightly
from MSHV, it shares common logic that is currently split across
separate conditional and build-time code paths, contributing to
fragmentation of the overall flow.
This change restructures the VM creation and initialization sequence
to better align shared logic, enforce scenario-specific ordering
constraints, and ensure consistent and correct behavior across all
supported configurations. In doing so, it restores proper CVM boot
behavior and improves the maintainability of the initialization code.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
c9cd82b52b