On Wed, Jun 27, 2018 at 06:06:04PM +0200, Ard Biesheuvel wrote:

Similar to the arm64 case, 64-bit x86 can benefit from using 32-bit
relative references rather than 64-bit absolute ones when emitting
struct jump_entry instances. Not only does this reduce the memory
footprint of the entries themselves by 50%, it also removes the need
for carrying relocation metadata on relocatable builds (i.e., for KASLR)
which saves a fair chunk of .init space as well (although the savings
are not as dramatic as on arm64)

This will conflict with:

  https://lkml.kernel.org/r/20180622172212.199633-10-namit at vmware.com