[$] The state of the page in 2023

The conversion of the kernel's memory-management subsystem over to folios was never going to be done in a day.At a plenary session at the start of the second day of the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Matthew Wilcox discussed the currentstate and future direction of this work. Quite a lot of progress has beenmade - and a lot of work remains to be done.