linux-kernel - Re: [PATCH v2 1/1] mm: skip mlocked THPs that are underused early in deferred_split

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: <fe2655f8-1f8c-467f-afd1-49da0d191744@gmail.com>
Date: Mon, 8 Sep 2025 10:28:17 -0400
From: Usama Arif <usamaarif642@...il.com>
To: Lance Yang <lance.yang@...ux.dev>, akpm@...ux-foundation.org,
 david@...hat.com
Cc: Liam.Howlett@...cle.com, baohua@...nel.org,
 baolin.wang@...ux.alibaba.com, dev.jain@....com,
 linux-kernel@...r.kernel.org, linux-mm@...ck.org,
 lorenzo.stoakes@...cle.com, npache@...hat.com, ryan.roberts@....com,
 ziy@...dia.com
Subject: Re: [PATCH v2 1/1] mm: skip mlocked THPs that are underused early in
 deferred_split_scan()



On 08/09/2025 10:07, Lance Yang wrote:
> From: Lance Yang <lance.yang@...ux.dev>
> 
> When we stumble over a fully-mapped mlocked THP in the deferred shrinker,
> it does not make sense to try to detect whether it is underused, because
> try_to_map_unused_to_zeropage(), called while splitting the folio, will not
> actually replace any zeroed pages by the shared zeropage.
> 
> Splitting the folio in that case does not make any sense, so let's not even
> scan to check if the folio is underused.
> 
> Suggested-by: David Hildenbrand <david@...hat.com>
> Signed-off-by: Lance Yang <lance.yang@...ux.dev>
Acked-by: Usama Arif <usamaarif642@...il.com>