It appears that most of their contributions were to the XFS filesystem. Which means it is not used by "everyone" in a very similar sense to the way in which ha

It appears that most of their contributions were to the XFS filesystem. Which means it is not used by "everyone" in a very similar sense to the way in which hardware drivers are not. I suspect that if "core" were defined to exclude hardware _and_ filesystem independent changes Oracle would not have been at the top of the list.