[to-be-updated] mm-sparse-vmemmap-open-code-init_compound_tail.patch removed from -mm tree

[to-be-updated] mm-sparse-vmemmap-open-code-init_compound_tail.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/sparse-vmemmap: open-code init_compound_tail()
has been removed from the -mm tree.  Its filename was
     mm-sparse-vmemmap-open-code-init_compound_tail.patch

This patch was dropped because an updated version will be issued

------------------------------------------------------
From: Muchun Song <songmuchun@bytedance.com>
Subject: mm/sparse-vmemmap: open-code init_compound_tail()
Date: Tue, 8 Sep 2026 11:03:27 +0800

init_compound_tail() is only used by vmemmap_shared_tail_page(), where the
shared tail page setup intentionally passes NULL as the compound head.

Keeping this helper in mm/internal.h exposes that special case to the rest
of the MM code and can make the NULL head argument look generally valid. 
Open-code the initialization at the only call site so the special-case use
stays local to sparse vmemmap optimization.  No functional change
intended.

Link:
https://lore.kernel.org/20260908030335.96549-4-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Qi Zheng <qi.zheng@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/internal.h       |    9 ---------
 mm/sparse-vmemmap.c |    5 ++++-
 2 files changed, 4 insertions(+), 10 deletions(-)

--- a/mm/internal.h~mm-sparse-vmemmap-open-code-init_compound_tail
+++ a/mm/internal.h
@@ -786,15 +786,6 @@ static inline void prep_compound_tail(st
 	VM_WARN_ON_ONCE(tail->private);
 }
 
-static inline void init_compound_tail(struct page *tail,
-		const struct page *head, unsigned int order, struct zone *zone)
-{
-	atomic_set(&tail->_mapcount, -1);
-	set_page_node(tail, zone_to_nid(zone));
-	set_page_zone(tail, zone_idx(zone));
-	prep_compound_tail(tail, head, order);
-}
-
 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
 
 /*
--- a/mm/sparse-vmemmap.c~mm-sparse-vmemmap-open-code-init_compound_tail
+++ a/mm/sparse-vmemmap.c
@@ -189,7 +189,10 @@ struct page __ref *vmemmap_shared_tail_p
 	for (int i = 0; i < PAGE_SIZE / sizeof(struct page); i++) {
 		page = (struct page *)addr + i;
 		mm_zero_struct_page(page);
-		init_compound_tail(page, NULL, order, zone);
+		atomic_set(&page->_mapcount, -1);
+		set_page_node(page, zone_to_nid(zone));
+		set_page_zone(page, zone_idx(zone));
+		prep_compound_tail(page, NULL, order);
 	}
 
 	page = virt_to_page(addr);
_

Patches currently in -mm which might be from songmuchun@bytedance.com are

mm-sparse-relax-struct-mem_section-size-constraints.patch
mm-sparse-vmemmap-rename-hvo-order-macros.patch
mm-mm_init-skip-initializing-shared-vmemmap-tail-pages.patch
mm-sparse-vmemmap-initialize-shared-tail-vmemmap-pages-on-allocation.patch
mm-sparse-vmemmap-support-section-based-vmemmap-accounting.patch
mm-mm_init-factor-out-pfn_to_zone.patch
mm-sparse-vmemmap-move-helpers-ahead-of-future-callers.patch
mm-sparse-vmemmap-support-section-based-vmemmap-optimization.patch
mm-sparse-initialize-memory-sections-earlier.patch
mm-hugetlb-switch-hugetlb-to-section-based-vmemmap-optimization.patch
mm-sparse-vmemmap-remove-sparsemem_vmemmap_preinit-support.patch
mm-sparse-inline-usemap-allocation-into-sparse_init_nid.patch
mm-sparse-remove-section_map_size.patch
mm-hugetlb-remove-huge_bootmem_hvo.patch
mm-hugetlb-remove-huge_bootmem_cma.patch
mm-hugetlb-localize-struct-huge_bootmem_page.patch
mm-hugetlb-localize-huge_bootmem_zones_valid.patch
mm-sparse-vmemmap-prepare-dax-vmemmap-population-for-section-orders.patch
mm-sparse-vmemmap-set-section-order-for-device-dax.patch
mm-sparse-vmemmap-switch-device-dax-to-shared-tail-vmemmap-pages.patch
mm-sparse-vmemmap-move-hvo-helpers-to-a-public-header.patch
powerpc-mm-switch-device-dax-to-shared-tail-vmemmap-pages.patch
mm-sparse-vmemmap-drop-the-extra-tail-page-from-device-dax-reservation.patch
mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch
documentation-mm-update-dax-vmemmap-deduplication-docs.patch