diff options
| -rw-r--r-- | Documentation/virtual/kvm/mmu.txt | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu.c | 26 |
2 files changed, 19 insertions, 11 deletions
diff --git a/Documentation/virtual/kvm/mmu.txt b/Documentation/virtual/kvm/mmu.txt index 3a4d681c3e98..daf9c0f742d2 100644 --- a/Documentation/virtual/kvm/mmu.txt +++ b/Documentation/virtual/kvm/mmu.txt @@ -203,10 +203,10 @@ Shadow pages contain the following information: page cannot be destroyed. See role.invalid. parent_ptes: The reverse mapping for the pte/ptes pointing at this page's spt. If - parent_ptes bit 0 is zero, only one spte points at this pages and + parent_ptes bit 0 is zero, only one spte points at this page and parent_ptes points at this single spte, otherwise, there exists multiple sptes pointing at this page and (parent_ptes & ~0x1) points at a data - structure with a list of parent_ptes. + structure with a list of parent sptes. unsync: If true, then the translations in this page may not match the guest's translation. This is equivalent to the state of the tlb when a pte is diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 3104748eeb48..5b249d4f4da1 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1098,17 +1098,23 @@ struct rmap_iterator { static u64 *rmap_get_first(struct kvm_rmap_head *rmap_head, struct rmap_iterator *iter) { + u64 *sptep; + if (!rmap_head->val) return NULL; if (!(rmap_head->val & 1)) { iter->desc = NULL; - return (u64 *)rmap_head->val; + sptep = (u64 *)rmap_head->val; + goto out; } iter->desc = (struct pte_list_desc *)(rmap_head->val & ~1ul); iter->pos = 0; - return iter->desc->sptes[iter->pos]; + sptep = iter->desc->sptes[iter->pos]; +out: + BUG_ON(!is_shadow_present_pte(*sptep)); + return sptep; } /* @@ -1118,14 +1124,14 @@ static u64 *rmap_get_first(struct kvm_rmap_head *rmap_head, */ static u64 *rmap_get_next(struct rmap_iterator *iter) { + u64 *sptep; + if (iter->desc) { if (iter->pos < PTE_LIST_EXT - 1) { - u64 *sptep; - ++iter->pos; sptep = iter->desc->sptes[iter->pos]; if (sptep) - return sptep; + goto out; } iter->desc = iter->desc->more; @@ -1133,17 +1139,20 @@ static u64 *rmap_get_next(struct rmap_iterator *iter) if (iter->desc) { iter->pos = 0; /* desc->sptes[0] cannot be NULL */ - return iter->desc->sptes[iter->pos]; + sptep = iter->desc->sptes[iter->pos]; + goto out; } } return NULL; +out: + BUG_ON(!is_shadow_present_pte(*sptep)); + return sptep; } #define for_each_rmap_spte(_rmap_head_, _iter_, _spte_) \ for (_spte_ = rmap_get_first(_rmap_head_, _iter_); \ - _spte_ && ({BUG_ON(!is_shadow_present_pte(*_spte_)); 1;}); \ - _spte_ = rmap_get_next(_iter_)) + _spte_; _spte_ = rmap_get_next(_iter_)) static void drop_spte(struct kvm *kvm, u64 *sptep) { @@ -1358,7 +1367,6 @@ static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head) bool flush = false; while ((sptep = rmap_get_first(rmap_head, &iter))) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); rmap_printk("%s: spte %p %llx.\n", __func__, sptep, *sptep); drop_spte(kvm, sptep); |