KVM: x86: Fix page-tables reserved bits

KVM does not handle the reserved bits of x86 page tables correctly:
In PAE, bits 5:8 are reserved in the PDPTE.
In IA-32e, bit 8 is not reserved.
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/mmu.c

@@ -3538,7 +3538,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
 	case PT32E_ROOT_LEVEL:
 		context->rsvd_bits_mask[0][2] =
 			rsvd_bits(maxphyaddr, 63) |
-			rsvd_bits(7, 8) | rsvd_bits(1, 2);	/* PDPTE */
+			rsvd_bits(5, 8) | rsvd_bits(1, 2);	/* PDPTE */
 		context->rsvd_bits_mask[0][1] = exb_bit_rsvd |
 			rsvd_bits(maxphyaddr, 62);	/* PDE */
 		context->rsvd_bits_mask[0][0] = exb_bit_rsvd |
@@ -3550,9 +3550,9 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
 		break;
 	case PT64_ROOT_LEVEL:
 		context->rsvd_bits_mask[0][3] = exb_bit_rsvd |
-			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
+			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7);
 		context->rsvd_bits_mask[0][2] = exb_bit_rsvd |
-			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
+			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7);
 		context->rsvd_bits_mask[0][1] = exb_bit_rsvd |
 			rsvd_bits(maxphyaddr, 51);
 		context->rsvd_bits_mask[0][0] = exb_bit_rsvd |