KVM: MMU: only update unsync page in invlpg path
Only unsync pages need updated at invlpg time since other shadow
pages are write-protected
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 22f1379..0671d7a 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -461,6 +461,7 @@
static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
{
struct kvm_shadow_walk_iterator iterator;
+ struct kvm_mmu_page *sp;
gpa_t pte_gpa = -1;
int level;
u64 *sptep;
@@ -472,10 +473,13 @@
level = iterator.level;
sptep = iterator.sptep;
+ sp = page_header(__pa(sptep));
if (is_last_spte(*sptep, level)) {
- struct kvm_mmu_page *sp = page_header(__pa(sptep));
int offset, shift;
+ if (!sp->unsync)
+ break;
+
shift = PAGE_SHIFT -
(PT_LEVEL_BITS - PT64_LEVEL_BITS) * level;
offset = sp->role.quadrant << shift;
@@ -493,7 +497,7 @@
break;
}
- if (!is_shadow_present_pte(*sptep))
+ if (!is_shadow_present_pte(*sptep) || !sp->unsync_children)
break;
}
