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From: "Jürgen Groß" <jgross@suse.com>
To: Zi Yan <ziy@nvidia.com>, David Hildenbrand <david@kernel.org>,
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Subject: Re: [PATCH RFC 00/14] Remove PG_private by using page/folio->private checks instead
Date: Mon, 3 Aug 2026 11:07:39 +0200	[thread overview]
Message-ID: <5ca4d0e4-1747-45a7-a916-a7516bb1692b@suse.com> (raw)
In-Reply-To: <20260731-remove-pg_private-v1-0-142c97ba3562@nvidia.com>


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On 01.08.26 04:13, Zi Yan wrote:
> Hi all,
> 
> This patchset removes PG_private to make space for upcoming PG_folio
> (reserved as __PG_folio) for identifying pages from a folio (more details
> in Note below). Instead of checking PG_private, all code is changed to
> check page/folio->private != NULL instead.

I'm a little bit worried that page/folio->private is in a union, so today
it could (in theory) be != NULL while PG_private isn't set.

Is it really not possible to enter a path where PG_private is tested while
page/folio->private != NULL due to the union being used otherwise (PG_private
not set)?


Juergen

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  parent reply	other threads:[~2026-08-03  9:07 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-01  2:13 [PATCH RFC 00/14] Remove PG_private by using page/folio->private checks instead Zi Yan
2026-08-01  2:13 ` [PATCH RFC 14/14] mm/page-flags: remove PG_private Zi Yan
2026-08-03  9:07 ` Jürgen Groß [this message]
2026-08-03 18:13   ` [PATCH RFC 00/14] Remove PG_private by using page/folio->private checks instead Zi Yan

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