linux-kernel - Re: [PATCH v4 3/4] mm: Support batched unmap for lazyfree large folios during reclamation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAGsJ_4w5Obx9=P0wkrbLaDzKpG0e-7xs7jgHRa91KO7e92MO8g@mail.gmail.com>
Date: Fri, 27 Jun 2025 09:46:37 +1200
From: Barry Song <21cnbao@...il.com>
To: Lance Yang <ioworker0@...il.com>
Cc: david@...hat.com, akpm@...ux-foundation.org, baolin.wang@...ux.alibaba.com, 
	chrisl@...nel.org, kasong@...cent.com, lance.yang@...ux.dev, 
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org, 
	linux-mm@...ck.org, linux-riscv@...ts.infradead.org, 
	lorenzo.stoakes@...cle.com, ryan.roberts@....com, v-songbaohua@...o.com, 
	x86@...nel.org, ying.huang@...el.com, zhengtangquan@...o.com
Subject: Re: [PATCH v4 3/4] mm: Support batched unmap for lazyfree large
 folios during reclamation

On Thu, Jun 26, 2025 at 9:29 PM Lance Yang <ioworker0@...il.com> wrote:
>
[...]
> +
> +               /*
> +                * If we are sure that we batched the entire folio and cleared
> +                * all PTEs, we can just optimize and stop right here.
> +                */
> +               if (nr_pages == folio_nr_pages(folio))

David also mentioned if (nr_pages > 1 && nr_pages == folio_nr_pages(folio)).
I assume it’s still fine when nr_pages == 1 for small folios? No?

>                         goto walk_done;
>                 continue;
>  walk_abort:
> --
>

Thanks,
Lance