+ mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix.patch added to mm-unstable branch

+ mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix.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-remove-head-variable-in-do_migrate_range-fix.patch

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

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------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix
Date: Mon Aug 19 10:36:53 PM PDT 2024

revise comment, per Jonathan

Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory_hotplug.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/mm/memory_hotplug.c~mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix
+++ a/mm/memory_hotplug.c
@@ -1788,10 +1788,10 @@ static void do_migrate_range(unsigned lo
 		folio = page_folio(page);
 
 		/*
-		 * The folio hold no reference or lock, it might be changed
-		 * concurrently(eg, split), folio_nr_pages() may read garbage,
-		 * but out loop could handle that as it revisits the split
-		 * folio later.
+		 * No reference or lock is held on the folio, so it might
+		 * be modified concurrently (e.g. split).  As such,
+		 * folio_nr_pages() may read garbage.  This is fine as the outer
+		 * loop will revisit the split folio later.
 		 */
 		if (folio_test_large(folio)) {
 			pfn = folio_pfn(folio) + folio_nr_pages(folio) - 1;
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

include-linux-mmzoneh-clean-up-watermark-accessors.patch
mm-memory_hotplug-remove-head-variable-in-do_migrate_range-fix.patch
fault-inject-improve-build-for-config_fault_injection=n-fix.patch
fault-inject-improve-build-for-config_fault_injection=n-fix-2.patch
fault-inject-improve-build-for-config_fault_injection=n-fix-3.patch