KVM: x86: trap invlpg

With pages out of sync invlpg needs to be trapped. For now simply nuke
the entry.

Untested on AMD.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 776fb6d2fd81..dc169e8148b1 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -461,6 +461,31 @@ out_unlock:
         return 0;
 }
 
+static int FNAME(shadow_invlpg_entry)(struct kvm_shadow_walk *_sw,
+                                      struct kvm_vcpu *vcpu, u64 addr,
+                                      u64 *sptep, int level)
+{
+
+        if (level == PT_PAGE_TABLE_LEVEL) {
+                if (is_shadow_present_pte(*sptep))
+                        rmap_remove(vcpu->kvm, sptep);
+                set_shadow_pte(sptep, shadow_trap_nonpresent_pte);
+                return 1;
+        }
+        if (!is_shadow_present_pte(*sptep))
+                return 1;
+        return 0;
+}
+
+static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
+{
+        struct shadow_walker walker = {
+                .walker = { .entry = FNAME(shadow_invlpg_entry), },
+        };
+
+        walk_shadow(&walker.walker, vcpu, gva);
+}
+
 static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr)
 {
         struct guest_walker walker;