Re: [RESEND RFC PATCH v2 0/5] mm/damon: add mTHP collapse and split actions

[wang lian]

Hi Lorenzo,

> On Jul 2, 2026, at 18:23, Lorenzo Stoakes <ljs@xxxxxxxxxx> wrote:
> 
> +cc all those you missed.
> 
> I really need to write a bot to do this, because I'm getting a little tired of
> pointing this out :))
> 
> On Thu, Jul 02, 2026 at 05:46:28PM +0800, Lian Wang wrote:
>> include/linux/damon.h      |  10 +++
>> include/linux/khugepaged.h |   9 +++
>> mm/damon/core.c            |   2 +
>> mm/damon/sysfs-schemes.c   |  77 ++++++++++++++++++++++
>> mm/damon/vaddr.c           | 128 +++++++++++++++++++++++++++++++++++++
>> mm/khugepaged.c            |  46 +++++++++++++
>> 6 files changed, 272 insertions(+)
> 
> You are doing damon changes, and that belongs to SJ, sure.
> 
> But you're also changing core THP code? Please ensure you cc- THP people because
> without our approval this cannot be merged:
> 
> $ scripts/get_maintainer.pl 20260702094633.75658-1-lianux.mm@xxxxxxxxxxxxx
> SJ Park <sj@xxxxxxxxxx> (maintainer:DAMON)
> Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> (maintainer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> David Hildenbrand <david@xxxxxxxxxx> (maintainer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Lorenzo Stoakes <ljs@xxxxxxxxxx> (maintainer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Zi Yan <ziy@xxxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> "Liam R. Howlett" <liam@xxxxxxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Nico Pache <npache@xxxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Ryan Roberts <ryan.roberts@xxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Dev Jain <dev.jain@xxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Barry Song <baohua@xxxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> Lance Yang <lance.yang@xxxxxxxxx> (reviewer:MEMORY MANAGEMENT - THP (TRANSPARENT HUGE PAGE))
> damon@xxxxxxxxxxxxxxx (open list:DAMON)
> linux-mm@xxxxxxxxx (open list:DAMON)
> linux-kernel@xxxxxxxxxxxxxxx (open list)
> 
>> 
>> --
>> 2.50.1 (Apple Git-155)
>> 
> 
Thank you for pointing this out again, and I deeply appreciate
all the tedious work you do as a maintainer to keep the mailing
lists aligned.

As a newcomer trying to transition into complex feature
development, I must admit my initial design is far from perfect.
I leveraged AI tools to assist with certain implementation
paths, and although I extensively self-reviewed, tested, and
reasoned through every single line of code, your and SJ's
feedback clearly shows there are still major architectural
flaws.  Just like my very first kernel patch -- which was
strictly reviewed and guided by you and David H. -- I know that
your sharp feedback is exactly what will help me grow as a
kernel engineer.

I will completely step back and radically rethink the design of
this series, especially regarding the cross-subsystem
encapsulation and locking hazards.

As for that bot you mentioned getting tired of running manually
-- let me write it for you.  An imperfect newcomer who just made
these exact mistakes knows precisely where the traps are.  I can
craft a pre-flight patch check script or a CI bot that
automatically validates the get_maintainer.pl output against the
patch file diffstat before any email is dispatched, throwing a
loud warning if core MM files are touched but their respective
maintainers are missing from the CC line.

What do you think?  I would love to build this tool to save your
and other maintainers' valuable time in the future.

Thanks again for steering me in the right direction!

Best regards,
Wang Lian
> Thanks, Lorenzo