diff options
| -rw-r--r-- | arch/x86/kvm/svm/nested.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index bf1e1ca22d9c..b191c6cab57d 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -837,8 +837,16 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) V_NMI_BLOCKING_MASK); } - /* Copied from vmcb01. msrpm_base can be overwritten later. */ - vmcb02->control.misc_ctl = vmcb01->control.misc_ctl; + /* + * Copied from vmcb01. msrpm_base can be overwritten later. + * + * SVM_MISC_ENABLE_NP in vmcb12 is only used for consistency checks. If + * L1 enables NPTs, KVM shadows L1's NPTs and uses those to run L2. If + * L1 disables NPT, KVM runs L2 with the same NPTs used to run L1. For + * the latter, L1 runs L2 with shadow page tables that translate L2 GVAs + * to L1 GPAs, so the same NPTs can be used for L1 and L2. + */ + vmcb02->control.misc_ctl = vmcb01->control.misc_ctl & SVM_MISC_ENABLE_NP; vmcb02->control.iopm_base_pa = vmcb01->control.iopm_base_pa; vmcb02->control.msrpm_base_pa = vmcb01->control.msrpm_base_pa; vmcb_mark_dirty(vmcb02, VMCB_PERM_MAP); |