On Wed, Sep 07, 2022 at 10:47:39AM -0300, Jason Gunthorpe wrote: > Would you be happier if we wrote it like > > #define IOMMU_EINCOMPATIBLE_DEVICE xx > > Which tells "which of the function parameters is actually invalid" ? Having done some Rust hacking in the last months, I have to say I like to concept of error handling with Result<> there. Ideally we have a way to emulate that in our C code without having to change all callers. What I am proposing is a way this could be emulated here, but I am open to other suggestions. Still better than re-using random error codes for special purposes. Regards, Joerg