From: LinFeng <linfeng23@xxxxxxxxxx>
Just adding !is_zero_page() to kvm_is_reserved_pfn() is too
rough. According to commit:e433e83bc3("KVM: MMU: Do not treat
ZONE_DEVICE pages as being reserved"), special handling in some
other flows is also need by zero_page, if not treat zero_page as
being reserved.
Signed-off-by: LinFeng <linfeng23@xxxxxxxxxx>
Signed-off-by: Zhuang Yanying <ann.zhuangyanying@xxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 2 ++
virt/kvm/kvm_main.c | 6 +++---
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 732c0270a489..e8db17d87c1a 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2961,6 +2961,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
* here.
*/
if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn) &&
+ !is_zero_pfn(pfn) &&
level == PT_PAGE_TABLE_LEVEL &&
PageTransCompoundMap(pfn_to_page(pfn)) &&
!mmu_gfn_lpage_is_disallowed(vcpu, gfn, PT_DIRECTORY_LEVEL)) {
@@ -5010,6 +5011,7 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
*/
if (sp->role.direct &&
!kvm_is_reserved_pfn(pfn) &&
+ !is_zero_pfn(pfn) &&
PageTransCompoundMap(pfn_to_page(pfn))) {
drop_spte(kvm, sptep);
need_tlb_flush = 1;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 7f7c22a687c0..fc0446bb393b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1660,7 +1660,7 @@ static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
if (is_error_noslot_pfn(pfn))
return KVM_ERR_PTR_BAD_PAGE;
- if (kvm_is_reserved_pfn(pfn)) {
+ if (kvm_is_reserved_pfn(pfn) && is_zero_pfn(pfn)) {
WARN_ON(1);
return KVM_ERR_PTR_BAD_PAGE;
}
@@ -1719,7 +1719,7 @@ static void kvm_release_pfn_dirty(kvm_pfn_t pfn)
void kvm_set_pfn_dirty(kvm_pfn_t pfn)
{
- if (!kvm_is_reserved_pfn(pfn)) {
+ if (!kvm_is_reserved_pfn(pfn) && !is_zero_pfn(pfn)) {
struct page *page = pfn_to_page(pfn);
if (!PageReserved(page))
@@ -1730,7 +1730,7 @@ EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
void kvm_set_pfn_accessed(kvm_pfn_t pfn)
{
- if (!kvm_is_reserved_pfn(pfn))
+ if (!kvm_is_reserved_pfn(pfn) && !is_zero_pfn(pfn))
mark_page_accessed(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
--
2.23.0
