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Date: Fri, 7 Jun 2024 21:27:38 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: linux-mm@kvack.org, Vlastimil Babka <vbabka@suse.cz>,
 "Vishal Moola (Oracle)" <vishal.moola@gmail.com>, Omar Sandoval
 <osandov@osandov.com>, David Hildenbrand <david@redhat.com>,
 "Matthew Wilcox (Oracle)" <willy@infradead.org>, Hao Ge <gehao@kylinos.cn>,
 linux-debuggers@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4] mm: convert page type macros to enum
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On Fri,  7 Jun 2024 13:29:53 -0700 Stephen Brennan <stephen.s.brennan@oracle.com> wrote:

> Changing PG_slab from a page flag to a page type in commit 46df8e73a4a3
> ("mm: free up PG_slab") in has the unintended consequence of removing
> the PG_slab constant from kernel debuginfo. The commit does add the
> value to the vmcoreinfo note, which allows debuggers to find the value
> without hardcoding it. However it's most flexible to continue
> representing the constant with an enum. To that end, convert the page
> type fields into an enum. Debuggers will now be able to detect that
> PG_slab's type has changed from enum pageflags to enum pagetype.
> 
> Fixes: 46df8e73a4a3 ("mm: free up PG_slab")

Should we backport this into 6.9.x?