It is perfectly valid for a guest to do VMXON and not do VMPTRLD. This state needs to be preserved on migration. Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> --- arch/x86/kvm/vmx.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index d3297fadf7ed..25a25fff8dd9 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -14482,13 +14482,6 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, if (!page_address_valid(vcpu, kvm_state->vmx.vmxon_pa)) return -EINVAL; - if (kvm_state->size < sizeof(kvm_state) + sizeof(*vmcs12)) - return -EINVAL; - - if (kvm_state->vmx.vmcs_pa == kvm_state->vmx.vmxon_pa || - !page_address_valid(vcpu, kvm_state->vmx.vmcs_pa)) - return -EINVAL; - if ((kvm_state->vmx.smm.flags & KVM_STATE_NESTED_SMM_GUEST_MODE) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) return -EINVAL; @@ -14510,6 +14503,14 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, if (ret) return ret; + /* Empty 'VMXON' state is permitted */ + if (kvm_state->size < sizeof(kvm_state) + sizeof(*vmcs12)) + return 0; + + if (kvm_state->vmx.vmcs_pa == kvm_state->vmx.vmxon_pa || + !page_address_valid(vcpu, kvm_state->vmx.vmcs_pa)) + return -EINVAL; + set_current_vmptr(vmx, kvm_state->vmx.vmcs_pa); if (kvm_state->vmx.smm.flags & KVM_STATE_NESTED_SMM_VMXON) { -- 2.14.4