[PATCH mmotm 00/15] mm: assorted small fixes and cleanups

[Hugh Dickins <hughd@google.com>]

Andrew, I'm about to trickle through the first six of probably fifteen
patches, diffed against against top of next-20220301, equally applicable
to mmotm 2022-02-28-14-45 (sorry, not looked at 2022-03-02-16-53 yet).

These are independent patches, which may be applied or dropped as you
wish: I'm not numbering them N/15, and I'm Cc'ing different interested
parties on the different patches.

More to come later today or tomorrow or after, I'm still updating
commit messages and Cc-lists for the rebased and retested patches: many
of which go back years, never quite reaching priority for posting until
now.  I'd hoped to send them earlier in the cycle, but mm/munlock took
precedence - and the first I'll send is a fix to an issue there.

Thanks,
Hugh