Re: [PATCH v2 00/16] mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries

Hugh Dickins
2025-11-11T04:07:51Z

On Mon, 10 Nov 2025, Andrew Morton wrote:
> On Mon, 10 Nov 2025 15:38:55 -0800 (PST) Hugh Dickins <hughd@google.com> wrote:
>
> > > I'm sorry but this is not a reasonable request. I am being as empathetic and
> > > kind as I can be here, but this series is proceeding without arbitrary delay.
> > >
> > > I will do everything I can to accommodate any concerns or issues you may have
> > > here _within reason_ :)
> >
> > But Lorenzo, have you even tested your series properly yet, with
> > swapping and folio migration and huge pages and tmpfs under load?
> > Please do.
> >
> > I haven't had time to bisect yet, maybe there's nothing more needed
> > than a one-liner fix somewhere; but from my experience it is not yet
> > ready for inclusion in mm and next - it stops testing other folks' work.
> >
> > I haven't tried today's v3, but from the cover letter of differences,
> > it didn't look like much of importance is fixed since v2: which
> > (after a profusion of "Bad swap offet entry 3ffffffffffff" messages,
> > not seen with v1, and probably not really serious) soon hits an Oops
> > or a BUG or something (as v1 did) - I don't have any logs or notes
> > to give yet, just forewarning before pursuing later in the day.
> >
> > If you think v3 has fixed real crashes under load, please say so:
> > otherwise, I doubt it's worth Andrew hurrying to replace v2 by v3.
>
> Oh. Thanks. I'll move the v3 series into mm-new for now.

Lorenzo, I can happily apologize: the v3 series in mm-everything-
2025-11-11-01-20 is a big improvement over v2 and v1, it is showing
none of the bad behaviours I saw with those. I've not searched or
compared for what actually fixed those symptoms (though have now
spotted mails from Shivank and Kairui regarding 3ffffffffffff),
I'm content now to move on to unrelated work...

Thanks,
Hugh