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Date: Wed, 20 Aug 2025 21:51:31 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: David Hildenbrand <david@redhat.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>, linux-mm
 <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>,
 richard.weiyang@gmail.com, Gerald Schaefer <gerald.schaefer@linux.ibm.com>,
 Heiko Carstens <hca@linux.ibm.com>, Vasily Gorbik <gor@linux.ibm.com>,
 Alexander Gordeev <agordeev@linux.ibm.com>, linux-s390
 <linux-s390@vger.kernel.org>
Subject: Re: [PATCH v4] mm: fix accounting of memmap pages
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	<687b556e-0196-4a38-986a-2e7b0308e03d@redhat.com>
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On Fri, 8 Aug 2025 16:23:52 +0200 David Hildenbrand <david@redhat.com> wrote:

> > @@ -567,6 +564,8 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
> >   				sparse_buffer_fini();
> >   				goto failed;
> >   			}
> > +			memmap_boot_pages_add(DIV_ROUND_UP(PAGES_PER_SECTION * sizeof(struct page),
> > +							   PAGE_SIZE));
> 
> IIRC, we can have partially populated boot sections, where only some 
> subsections actually have a memmap ... so this calculation is possibly 
> wrong in some cases.

The patch (which has cc:stable!) has been in state "stuck" for 12 days
due to "possibly wrong".  Could someone please find a way to get it
unstuck?