@marcan tbh I find this and related posts quite toxic. The IOMMU maintainers are nice guys (one of them is my team colleague) and they don't deserve to have people reading your posts getting the impression that their subsystem is crap.

In the thread you mention doing some unusual (or maybe first time) scenario with it. It's completely normal to encounter bugs in such situations and simply fix them along the way, no need to gloat about it.