KVM: MMU: check for present pdptr shadow page in walk_shadow

[linux-2.6-block.git] / arch / x86 / kvm / mmu.c

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 863baf70506eda1d21f6ef713e300a971296b7b5..641c07844e6eb7ce8a03f81cc057b611082f72ef 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1269,6 +1269,8 @@ static int walk_shadow(struct kvm_shadow_walk *walker,
        if (level == PT32E_ROOT_LEVEL) {
                shadow_addr = vcpu->arch.mmu.pae_root[(addr >> 30) & 3];
                shadow_addr &= PT64_BASE_ADDR_MASK;
+               if (!shadow_addr)
+                       return 1;
                --level;
        }