Linus refuses to accept new code that makes use of x86 segmentation, even if such usage involves a configurable option. So there will be no UDEREF/KERNEXEC in the mainline kernel. Little bits and pieces of other features/modifications may be picked up by people who read the patch (like the *_operations constifying -- though in vanilla this matters only for people using CONFIG_DEBUG_RODATA, or fixing up page protections on modules, etc) but we won't be committing them ourselves.
From time to time though we may/do submit bug reports if for instance, UDEREF or KERNEXEC catches a bug in the vanilla kernel. There's an example we saw recently where some module if given a parameter would attempt to modify some read-only memory, caught by KERNEXEC.