On Thu, Apr 07, 2022 at 03:12:57PM +0200, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > > > + if (static_call(kvm_x86_get_cpl)(vcpu) != 0) { > > > + ret = -KVM_EPERM; > > > + goto out; > > > + } > > Is this guaranteed by TDG.VP.VMCALL? Yes. TDCALL instruction in TD results in #GP(0) if CPL > 0. It's documented in trust domain CPU architectural extensions spec. https://www.intel.com/content/dam/develop/external/us/en/documents-tps/intel-tdx-cpu-architectural-specification.pdf Anyway VMM can't know TD guest CPL (or other CPU state). -- Isaku Yamahata <isaku.yamahata@xxxxxxxxx>