executor: isolate x86 page table pool to high memory in SYZOS

Refactor the SYZOS guest memory layout to decouple the dynamic page table
allocator from the fixed system data structures (GDT, IDT, initial PML4).
Previously, the page table pool was located at 0x5000, tightly packed with
the initial system pages. This rigid structure made it difficult to expand
the pool or inject configuration data without shifting fixed offsets.

Move X86_SYZOS_ADDR_PT_POOL to 0x180000, creating a distinct high-memory
region well above the L2 VCPU data, and increase the pool size to 64 pages
(256KB) to support deeper nested hierarchies.

Update the syz_kvm_setup_syzos_vm logic to handle non-contiguous
Guest-to-Host address translation via a new get_host_pte_ptr() helper.
This is necessary because the executor's host memory allocation remains
strictly linear while the guest physical address space now contains
significant gaps.

This layout change is a prerequisite for enabling "SYZOS inside SYZOS"
(L2 nesting), allowing the future injection of boot arguments into the
gap created between fixed data and dynamic regions.

0 files changed, 0 insertions, 0 deletions