Re: [PATCH 0/6] mm: preparatory patches for PMD level swap entries

[Andrew Morton <akpm@linux-foundation.org>]

On Fri,  3 Jul 2026 10:48:31 -0700 Usama Arif <usama.arif@linux.dev> wrote:

> On Tue, 30 Jun 2026 09:34:37 -0700 Usama Arif <usama.arif@linux.dev> wrote:
> 
> > This is the preparatory part of the PMD page table swapin work.  The
> > full PMD swap entry series has been split into two parts:
> > 
> >   1. this preparatory series, which contains the first 6 patches. Zi [1]
> >      and Lance [2] suggested to separate this out from the core series.
> >   2. the PMD swap entry core series, which depends on this one. I will
> >      send this once the preparatory series is merged in mm-new as v3
> >      as the combined is currently at v2 [1].
> >      I have not marked this prep series as v3, as its not really adding
> >      support for PMD swap entries.
> > 
> > This series does not introduce PMD swap entries and does not install any
> > new page-table entry type.  It only cleans up existing PMD softleaf
> > helpers and call sites so the follow-up PMD swap entry series can be
> > smaller and easier to review.
> > 
> 
> Hi Andrew,
> 
> The series only needs 2 small changes:
> 
> Removing a comment:
> https://lore.kernel.org/all/157838aa-1518-46b5-8734-feab2c42ee2a@kernel.org/
> 
> and s/CONFIG_ARCH_SUPPORTS_PMD/CONFIG_ARCH_HAS_PMD_SOFTLEAVES/
> in the last patch:
> https://lore.kernel.org/all/e37df165-8de0-4924-ba19-0d43a6b7d36e@kernel.org/
> 
> I am always torn between sending a fixlet on the existing series or a
> new revision.
> Just wanted to check what is easiest for you and your preference
> in situations like above?

Oh boy.

Historically my preference was for little fixups - so I and every one
else could see what changed.  Mainly to avoid invalidating prior review
efforts.  It's comforting to have the thing stabilized, unaltered and
to see the little fixies getting smaller and less frequent.

But this process tended to make people's heads spin - mainly, I
suspect, those who hadn't reviewed the earlier versions!

So nowadays if I receive a wholesale replacement I handle all this by
dropping v6, adding v7 then replying with a heres-what-you-changed
diff.  For the earlier reviewers and for author to double-check that
they really meant to do that.  I have yet to receive feedback about
this, of either polarity.

In this particular case, whatever you prefer.  If it's to be a full
replacement, please do include the v0->v1 summary below the ---
separator.