[PATCH v2 07/15] KVM: MMU: redesign the algorithm of pte_list

Change the algorithm to: 1) always add new desc to the first desc (pointed by parent_ptes/rmap) that is good to implement rcu-nulls-list-like lockless rmap walking 2) always move the entry in the first desc to the the position we want to remove when delete a spte in the parent_ptes/rmap

[PATCH v2 07/15] KVM: MMU: redesign the algorithm of pte_list

Change the algorithm to: 1) always add new desc to the first desc (pointed by parent_ptes/rmap) that is good to implement rcu-nulls-list-like lockless rmap walking 2) always move the entry in the first desc to the the position we want to remove when delete a spte in the parent_ptes/rmap