[PATCH] KVM: MMU: Use the guest pdptrs instead of mapping cr3 in pae mode

This lets us not write protect a partial page, and is anyway what a real
processor does.

Signed-off-by: Avi Kivity <avi@qumranet.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 4512d8c..68e121e 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1491,6 +1491,8 @@
 
 	mmu_reset_needed |= vcpu->cr4 != sregs->cr4;
 	kvm_arch_ops->set_cr4(vcpu, sregs->cr4);
+	if (!is_long_mode(vcpu) && is_pae(vcpu))
+		load_pdptrs(vcpu, vcpu->cr3);
 
 	if (mmu_reset_needed)
 		kvm_mmu_reset_context(vcpu);