Hi,
as posted in Unity 2017.2 Import Issue (Segfault) ,
there might be an issue when importing/running/installing UnityIAP on Linux.
It seems for some reason BillingMode.json is reloaded endlessly until the Editor Segfaults. This seems to make importing a Unity Project impossible unless the json file is deleted manually. After a trigger that rebuilds this file, the Editor starts hogging CPU again until it segfaults.
straces, diffs and Debugging Info are provided in the original post.