[PATCH 07/25] xen: Complete pagetable pinning for Xen

Xen has a notion of pinned pagetables, which are pagetables that remain read-only to the guest and are validated by the hypervisor. This makes context switches much cheaper, because the hypervisor doesn't need to revalidate the pagetable each time. This patch adds a PG_pinned flag for pagetable

[PATCH 07/25] xen: Complete pagetable pinning for Xen

Xen has a notion of pinned pagetables, which are pagetables that remain read-only to the guest and are validated by the hypervisor. This makes context switches much cheaper, because the hypervisor doesn't need to revalidate the pagetable each time. This patch adds a PG_pinned flag for pagetable