[$] A change in direction for security-module stacking?

The long-running effort to complete the work on stacking (or composing) the
Linux security modules (LSMs) recently encountered a barrier—in the form of
a "suggestion" to discontinue it from Linus Torvalds.  His complaint
revolved around the indirect function calls that are used to implement
LSMs, but he also did not think much of the effort to switch away from
those calls.  While it does not appear that a major course-change is in store
for LSMs, it is clear that Torvalds is not happy with the direction of that
subsystem.

https://lwn.net/Articles/970070/