On Thu, Mar 05, 2020 at 09:40:15AM -0800, Sean Christopherson wrote: > Would it make sense to add reserved fields to the structs so that new > features can be added in a backwards compatible way? E.g. if we want to > allow userspace to control the backing store by passing in a file > descriptor ENCLAVE_CREATE. It would not really be a huge win even if you did that since old software would not be aware of the new fields. Sounds somewhat messy to me. Even a new ioctl later on is in my opinion always a better option than reserved fields when you add ioctl's. /Jarkko
