KVM: MMU: check reserved bits only if CR4.PSE=1 or CR4.PAE=1

- Check reserved bits only if CR4.PAE=1 or CR4.PSE=1 when guest #PF occurs
- Fix a typo in reset_rsvds_bits_mask()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 064c3efb49dc..83d2ebce9ea9 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2297,13 +2297,19 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
                 /* no rsvd bits for 2 level 4K page table entries */
                 context->rsvd_bits_mask[0][1] = 0;
                 context->rsvd_bits_mask[0][0] = 0;
+                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0];
+
+                if (!is_pse(vcpu)) {
+                        context->rsvd_bits_mask[1][1] = 0;
+                        break;
+                }
+
                 if (is_cpuid_PSE36())
                         /* 36bits PSE 4MB page */
                         context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21);
                 else
                         /* 32 bits PSE 4MB page */
                         context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21);
-                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
                 break;
         case PT32E_ROOT_LEVEL:
                 context->rsvd_bits_mask[0][2] =
@@ -2316,7 +2322,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
                 context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
                         rsvd_bits(maxphyaddr, 62) |
                         rsvd_bits(13, 20);              /* large page */
-                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
+                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0];
                 break;
         case PT64_ROOT_LEVEL:
                 context->rsvd_bits_mask[0][3] = exb_bit_rsvd |
@@ -2334,7 +2340,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
                 context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
                         rsvd_bits(maxphyaddr, 51) |
                         rsvd_bits(13, 20);              /* large page */
-                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
+                context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0];
                 break;
         }
 }