Re: [PATCH v3 3/5] mm: madvise: implement lightweight guard page mechanism

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Fri, Oct 25, 2024 at 05:11:31PM -0700, Andrew Morton wrote:
> On Thu, 24 Oct 2024 08:25:46 +0100 Lorenzo Stoakes <lorenzo.stoakes@oracle.com> wrote:
>
> > I actually do plan to extend this work to support shmem and file-backed
> > mappings in the future as a revision to this work.
>
> Useful, thanks.  I pasted this in.
>
> > >
> > > (generally, it would be nice to include the proposed manpage update at
> > > this time, so people can review it while the code change is fresh in
> > > their minds)
> >
> > It'd be nice to have the man pages live somewhere within the kernel so we
> > can do this as part of the patch change as things evolve during review, but
> > obviously moving things about like that is out of scope for this discussion
> > :)
>
> Yes, that would be good.  At present the linkage is so poor that things
> could get lost.

Things _have_ got lost. I don't see MADV_DONTNEED_LOCKED in the madvise()
man page for instance...

(I intend actually to send a patch for that alongside my changes.)

>
> I guess one thing we could do is to include the proposed manpage update
> within the changelogs.  That way it's stored somewhere and gets reviewed
> alongside the patches themselves.

Hm it won't be a diff but I do like the idea... let me come up with
something.

>
> > I do explicitly intend to send a manpage update once this series lands
> > however.
>
> That's late, IMO.  Sometimes reviewing manpage updates leads people to
> ask "hey.  what about X" or "hey, that's wrong".  Michael Kerrisk was
> good at finding such holes, back in the day.
>

Right, this is the problem with having the manpages in a separate repo, it
seems presumptious to _assume_ this will land in 6.13 though I hope it
does, but if I get a patch accepted in the manpages they may ship a version
that has information that is simply invalid...

Really would be nice to integrate it here :)

Michael Kerrisk is a hero, writes with a power of clarity I could only
dream of :) understandable that he may be rather tired of having to
maintain all this however...