+ mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page.patch added to mm-new branch

+ mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: mm/memory_hotplug: drop CONFIG_HAVE_ARCH_PFN_VALID handling from pfn_to_online_page()
has been added to the -mm mm-new branch.  Its filename is
     mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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and is updated there most days

------------------------------------------------------
From: "David Hildenbrand (Arm)" <david@kernel.org>
Subject: mm/memory_hotplug: drop CONFIG_HAVE_ARCH_PFN_VALID handling from pfn_to_online_page()
Date: Mon, 21 Sep 2026 21:59:05 +0200

Drop CONFIG_HAVE_ARCH_PFN_VALID handling, as CONFIG_HAVE_ARCH_PFN_VALID is
never used with CONFIG_MEMORY_HOTPLUG, as the latter depends on
CONFIG_SPARSEMEM_VMEMMAP.  Make sure it stays that way.

Link: https://lore.kernel.org/20260921-b4-sparsemem_cleanups-v2-13-54d81d65e125@kernel.org
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Qi Zheng <qi.zheng@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Danilo Krummrich <dakr@kernel.org>
---

 mm/memory_hotplug.c |    9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

--- a/mm/memory_hotplug.c~mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page
+++ a/mm/memory_hotplug.c
@@ -345,6 +345,8 @@ struct page *pfn_to_online_page(unsigned
 	struct dev_pagemap *pgmap;
 	struct mem_section *ms;
 
+	BUILD_BUG_ON(IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID));
+
 	if (nr >= NR_MEM_SECTIONS)
 		return NULL;
 
@@ -352,13 +354,6 @@ struct page *pfn_to_online_page(unsigned
 	if (!online_section(ms))
 		return NULL;
 
-	/*
-	 * Save some code text when online_section() +
-	 * pfn_section_valid() are sufficient.
-	 */
-	if (IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID) && !pfn_valid(pfn))
-		return NULL;
-
 	if (!pfn_section_valid(ms, pfn))
 		return NULL;
 
_

Patches currently in -mm which might be from david@kernel.org are

maintainers-split-up-memory-management-memory-policy-and-migration.patch
maintainers-move-memory-tiering-under-memory-management-numa-placement.patch
maintainers-make-gregory-a-co-maintainer-of-memory-management-numa-placement.patch
selftests-mm-khugepaged-remove-str_dup-usage.patch
mm-sparse-move-mem_section-init-to-sparse_extreme_init.patch
mm-sparse-refactor-sparse_sections_init.patch
mm-sparse-move-initialization-of-section-metadata-to-sparse_metadata_init.patch
mm-sparse-rename-and-cleanup-sparse_init_nid.patch
mm-sparse-cleanup-sparse_init_one_section.patch
mm-sparse-rename-__highest_present_section_nr-to-__highest_used_section_nr.patch
mm-sparse-remove-pfn_in_present_section.patch
mm-sparse-move-__highest_used_section_nr-handling.patch
scripts-gdb-mmpy-remove-fallbacks-for-section_has_mem_map-and-section_is_early.patch
mm-sparse-remove-section_marked_present.patch
mm-sparse-remove-flags-parameter-from-sparse_init_one_section.patch
fs-proc-page-clarify-comment-in-get_max_dump_pfn.patch
mm-memory_hotplug-drop-config_have_arch_pfn_valid-handling-from-pfn_to_online_page.patch