[$] Memory-management changes for CXL

Kyungsan Kim began his talk at the 2023Linux Storage, Filesystem, Memory-Management and BPF Summit with aclaim that the Compute Express Link (CXL) technology is leading tofundamental changes in computer architecture. The kernel will have torespond with changes of its own, including in its memory-management layer.Drawing on some experience gained at Samsung, Kim had a few suggestions onthe form those changes should take - suggestions that ran into somedisagreement from other memory-management developers.