As comment in code specifies, SMM temporarily disables VMX so we cannot be in guest mode, nor can VMLAUNCH/VMRESUME be pending. However, code currently assumes that these are the only flags that can be set on kvm_state->flags. This is not true as KVM_STATE_NESTED_EVMCS can also be set on this field to signal that eVMCS should be enabled. Therefore, fix code to check for guest-mode and pending VMLAUNCH/VMRESUME explicitly. Reviewed-by: Joao Martins <joao.m.martins@xxxxxxxxxx> Signed-off-by: Liran Alon <liran.alon@xxxxxxxxxx> --- arch/x86/kvm/vmx/nested.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 5c470db311f7..27ff04874f67 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5373,7 +5373,10 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, * nor can VMLAUNCH/VMRESUME be pending. Outside SMM, SMM flags * must be zero. */ - if (is_smm(vcpu) ? kvm_state->flags : kvm_state->hdr.vmx.smm.flags) + if (is_smm(vcpu) ? + (kvm_state->flags & + (KVM_STATE_NESTED_GUEST_MODE | KVM_STATE_NESTED_RUN_PENDING)) + : kvm_state->hdr.vmx.smm.flags) return -EINVAL; if ((kvm_state->hdr.vmx.smm.flags & KVM_STATE_NESTED_SMM_GUEST_MODE) && -- 2.20.1
