&gt; So, why haven&#x27;t they been?<p>Grsec upstream argues that only accepting part of the whole is worse than having their patches outside mainline in bulk, because it would give developers and users a <i>false</i> sense of security to only provide <i>some</i> of the hardening grsec does.<p>See this[1] LWN article from 2009, which is a kernel developers post with a comment retort by some grsec developers.<p>[1]: <a href="https:&#x2F;&#x2F;lwn.net&#x2F;Articles&#x2F;313621&#x2F;" rel="nofollow">https:&#x2F;&#x2F;lwn.net&#x2F;Articles&#x2F;313621&#x2F;</a><p>The frustration is that we are now seven years later and the situation has only gotten worse - plenty of kernel exploits have emerged, no distro is shipping grsec comprehensively, grsec itself had to stop providing stable releases, and it has become more religious than logical as to why many critical features, like the internal bug prevention functionality, never will be mainlined and will be re-implemented with much less thoroughly tested surrogates.