KVM: MMU: update 'root_hpa' out of loop in PAE shadow path

The value of 'vcpu->arch.mmu.pae_root' is not modified, so we can update
'root_hpa' out of the loop.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index c94c432..3630046 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2393,8 +2393,8 @@
 			++sp->root_count;
 			spin_unlock(&vcpu->kvm->mmu_lock);
 			vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK;
-			vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
 		}
+		vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
 	} else
 		BUG();
 
@@ -2466,8 +2466,8 @@
 		spin_unlock(&vcpu->kvm->mmu_lock);
 
 		vcpu->arch.mmu.pae_root[i] = root | pm_mask;
-		vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
 	}
+	vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
 
 	/*
 	 * If we shadow a 32 bit page table with a long mode page