On 12/12/2017 17:07, Roman Kagan wrote: > + idx = srcu_read_lock(&vcpu->kvm->srcu); > + ret = kvm_vcpu_read_guest(vcpu, gpa, ¶m, sizeof(param)); > + srcu_read_unlock(&vcpu->kvm->srcu, idx); > + The lock/unlock is not needed (vcpu_enter_guest -> vmx_handle_exit -> handle_vmcall -> kvm_emulate_hypercall -> kvm_hv_hypercall -> kvm_hvcall_signal_event). I'll drop it. Thanks,