1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c
index 8bdb9ca1811c..9ff74805c7d1 100644
--- a/drivers/kvm/mmu.c
+++ b/drivers/kvm/mmu.c
@@ -806,10 +806,12 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
         for (i = 0; i < 4; ++i) {
                 hpa_t root = vcpu->mmu.pae_root[i];
 
-                ASSERT(VALID_PAGE(root));
-                root &= PT64_BASE_ADDR_MASK;
-                page = page_header(root);
-                --page->root_count;
+                if (root) {
+                        ASSERT(VALID_PAGE(root));
+                        root &= PT64_BASE_ADDR_MASK;
+                        page = page_header(root);
+                        --page->root_count;
+                }
                 vcpu->mmu.pae_root[i] = INVALID_PAGE;
         }
         vcpu->mmu.root_hpa = INVALID_PAGE;
@@ -840,9 +842,13 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu)
                 hpa_t root = vcpu->mmu.pae_root[i];
 
                 ASSERT(!VALID_PAGE(root));
-                if (vcpu->mmu.root_level == PT32E_ROOT_LEVEL)
+                if (vcpu->mmu.root_level == PT32E_ROOT_LEVEL) {
+                        if (!is_present_pte(vcpu->pdptrs[i])) {
+                                vcpu->mmu.pae_root[i] = 0;
+                                continue;
+                        }
                         root_gfn = vcpu->pdptrs[i] >> PAGE_SHIFT;
-                else if (vcpu->mmu.root_level == 0)
+                } else if (vcpu->mmu.root_level == 0)
                         root_gfn = 0;
                 page = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
                                         PT32_ROOT_LEVEL, !is_paging(vcpu),