Actually, this isn't really a major problem. The page cache has a
32-bit byte offset field, but it could easily be made a 32-bit "sector"
offset, for example, giving you 41 bits to play with. It could also be
a 32-bit "page" offset, at which time you have 44 bits covered, but then
you couldn't do 1kB-aligned file mappings any more (and those are used
by some older binary formats).
>Gnu libc fortunately already has made provision for a larger off_t, so
>the main issue is the VM layer.
If that is really the main issue then we have no problems at all. By
the time 44 bits is a problem for files I sincerely hope that we can
ditch the old 32-bit architecture. All of these things are so much
easier on a 64-bit machine.
Linus