+ mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type.patch added to mm-hotfixes-unstable branch

+ mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: swap: remove duplicate nr_swap_pages decrement in get_swap_page_of_type()
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type.patch

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

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------------------------------------------------------
From: Youngjun Park <youngjun.park@lge.com>
Subject: mm: swap: remove duplicate nr_swap_pages decrement in get_swap_page_of_type()
Date: Sun, 2 Nov 2025 17:24:56 +0900

After commit 4f78252da887, nr_swap_pages is decremented in
swap_range_alloc(). Since cluster_alloc_swap_entry() calls
swap_range_alloc() internally, the decrement in get_swap_page_of_type()
causes double-decrementing.

Remove the duplicate decrement.

Link: https://lkml.kernel.org/r/20251102082456.79807-1-youngjun.park@lge.com
Fixes: 4f78252da887 ("mm: swap: move nr_swap_pages counter decrement from folio_alloc_swap() to swap_range_alloc()")
Signed-off-by: Youngjun Park <youngjun.park@lge.com>
Acked-by: Chris Li <chrisl@kernel.org>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Kairui Song <kasong@tencent.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: <stable@vger.kernel.org> [6.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swapfile.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/mm/swapfile.c~mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type
+++ a/mm/swapfile.c
@@ -2005,10 +2005,8 @@ swp_entry_t get_swap_page_of_type(int ty
 			local_lock(&percpu_swap_cluster.lock);
 			offset = cluster_alloc_swap_entry(si, 0, 1);
 			local_unlock(&percpu_swap_cluster.lock);
-			if (offset) {
+			if (offset)
 				entry = swp_entry(si->type, offset);
-				atomic_long_dec(&nr_swap_pages);
-			}
 		}
 		put_swap_device(si);
 	}
_

Patches currently in -mm which might be from youngjun.park@lge.com are

mm-swap-remove-duplicate-nr_swap_pages-decrement-in-get_swap_page_of_type.patch
mm-swap-fix-memory-leak-in-setup_clusters-error-path.patch
mm-swap-use-swp_solidstate-to-determine-if-swap-is-rotational.patch
mm-swap-remove-redundant-comment-for-read_swap_cache_async.patch
mm-swap-change-swap_alloc_slow-to-void.patch
mm-swap-remove-scan_swap_map_slots-references-from-comments.patch