(mmu->root_level >= PT64_ROOT_4LEVEL || mmu->direct_map)) {
mmu_free_root_page(kvm, &mmu->root_hpa, &invalid_list);
} else if (mmu->pae_root) {
- for (i = 0; i < 4; ++i)
- if (mmu->pae_root[i] != 0)
- mmu_free_root_page(kvm,
- &mmu->pae_root[i],
- &invalid_list);
+ for (i = 0; i < 4; ++i) {
+ if (!IS_VALID_PAE_ROOT(mmu->pae_root[i]))
+ continue;
+
+ mmu_free_root_page(kvm, &mmu->pae_root[i],
+ &invalid_list);
+ mmu->pae_root[i] = INVALID_PAE_ROOT;
+ }
}
mmu->root_hpa = INVALID_PAGE;
mmu->root_pgd = 0;
return -EIO;
for (i = 0; i < 4; ++i) {
- WARN_ON_ONCE(mmu->pae_root[i] &&
- VALID_PAGE(mmu->pae_root[i]));
+ WARN_ON_ONCE(IS_VALID_PAE_ROOT(mmu->pae_root[i]));
root = mmu_alloc_root(vcpu, i << (30 - PAGE_SHIFT),
i << 30, PT32_ROOT_LEVEL, true);
}
for (i = 0; i < 4; ++i) {
- WARN_ON_ONCE(mmu->pae_root[i] && VALID_PAGE(mmu->pae_root[i]));
+ WARN_ON_ONCE(IS_VALID_PAE_ROOT(mmu->pae_root[i]));
if (mmu->root_level == PT32E_ROOT_LEVEL) {
if (!(pdptrs[i] & PT_PRESENT_MASK)) {
- mmu->pae_root[i] = 0;
+ mmu->pae_root[i] = INVALID_PAE_ROOT;
continue;
}
root_gfn = pdptrs[i] >> PAGE_SHIFT;
for (i = 0; i < 4; ++i) {
hpa_t root = vcpu->arch.mmu->pae_root[i];
- if (root && VALID_PAGE(root)) {
+ if (IS_VALID_PAE_ROOT(root)) {
root &= PT64_BASE_ADDR_MASK;
sp = to_shadow_page(root);
mmu_sync_children(vcpu, sp);
mmu->pae_root = page_address(page);
for (i = 0; i < 4; ++i)
- mmu->pae_root[i] = INVALID_PAGE;
+ mmu->pae_root[i] = INVALID_PAE_ROOT;
return 0;
}
for (i = 0; i < 4; ++i) {
hpa_t root = vcpu->arch.mmu->pae_root[i];
- if (root && VALID_PAGE(root)) {
+ if (IS_VALID_PAE_ROOT(root)) {
root &= PT64_BASE_ADDR_MASK;
sp = to_shadow_page(root);
__mmu_spte_walk(vcpu, sp, fn, 2);
#define MMU_WARN_ON(x) do { } while (0)
#endif
+/*
+ * Unlike regular MMU roots, PAE "roots", a.k.a. PDPTEs/PDPTRs, have a PRESENT
+ * bit, and thus are guaranteed to be non-zero when valid. And, when a guest
+ * PDPTR is !PRESENT, its corresponding PAE root cannot be set to INVALID_PAGE,
+ * as the CPU would treat that as PRESENT PDPTR with reserved bits set. Use
+ * '0' instead of INVALID_PAGE to indicate an invalid PAE root.
+ */
+#define INVALID_PAE_ROOT 0
+#define IS_VALID_PAE_ROOT(x) (!!(x))
+
struct kvm_mmu_page {
struct list_head link;
struct hlist_node hash_link;