linux-kernel - Re: [PATCH] mm/ptdesc: Derive from the compound head in page

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] [day] [month] [year] [list]

Message-ID: <aRHq4OdBCtC_V0eS@casper.infradead.org>
Date: Mon, 10 Nov 2025 13:38:40 +0000
From: Matthew Wilcox <willy@...radead.org>
To: Anshuman Khandual <anshuman.khandual@....com>
Cc: linux-mm@...ck.org, vishal.moola@...il.com,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Hildenbrand <david@...hat.com>,
	Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
	"Liam R . Howlett" <Liam.Howlett@...cle.com>,
	Vlastimil Babka <vbabka@...e.cz>, Mike Rapoport <rppt@...nel.org>,
	Suren Baghdasaryan <surenb@...gle.com>,
	Michal Hocko <mhocko@...e.com>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mm/ptdesc: Derive from the compound head in page_ptdesc()

On Mon, Nov 10, 2025 at 06:37:25AM +0000, Anshuman Khandual wrote:
> struct ptdesc (including all relevant helpers) support multi order compound
> pages. But page_ptdesc() coverts given page into its own ptdesc rather than
> deriving from its compound head as would have been expected otherwise. Just
> change the macro to fetch the struct ptdesc from the compound head instead,
> so that the same struct ptdesc is reached from all tail pages.

Please review
https://lore.kernel.org/linux-mm/20251020001652.2116669-1-willy@infradead.org/
instead.