+ mm-huge_memory-fix-folio-split-stats-counting.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/huge_memory: fix folio split stats counting
has been added to the -mm mm-new branch.  Its filename is
     mm-huge_memory-fix-folio-split-stats-counting.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-huge_memory-fix-folio-split-stats-counting.patch

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

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patches, and acceptance into mm-new is a notification for others take
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------------------------------------------------------
From: Zi Yan <ziy@nvidia.com>
Subject: mm/huge_memory: fix folio split stats counting
Date: Wed, 26 Nov 2025 16:06:18 -0500

The "return <error code>" statements for error checks at the beginning of
__folio_split() skip necessary count_vm_event() and count_mthp_stat() at
the end of the function.  Fix these by replacing them with "ret = <error
code>; goto out;".

Link: https://lkml.kernel.org/r/20251126210618.1971206-5-ziy@nvidia.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: Balbir Singh <balbirs@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |   14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

--- a/mm/huge_memory.c~mm-huge_memory-fix-folio-split-stats-counting
+++ a/mm/huge_memory.c
@@ -3942,16 +3942,20 @@ static int __folio_split(struct folio *f
 	VM_WARN_ON_ONCE_FOLIO(!folio_test_locked(folio), folio);
 	VM_WARN_ON_ONCE_FOLIO(!folio_test_large(folio), folio);
 
-	if (folio != page_folio(split_at) || folio != page_folio(lock_at))
-		return -EINVAL;
+	if (folio != page_folio(split_at) || folio != page_folio(lock_at)) {
+		ret = -EINVAL;
+		goto out;
+	}
 
-	if (new_order >= old_order)
-		return -EINVAL;
+	if (new_order >= old_order) {
+		ret = -EINVAL;
+		goto out;
+	}
 
 	ret = folio_check_splittable(folio, new_order, split_type);
 	if (ret) {
 		VM_WARN_ONCE(ret == -EINVAL, "Tried to split an unsplittable folio");
-		return ret;
+		goto out;
 	}
 
 	if (is_anon) {
_

Patches currently in -mm which might be from ziy@nvidia.com are

mm-huge_memory-change-folio_split_supported-to-folio_check_splittable.patch
mm-huge_memory-replace-can_split_folio-with-direct-refcount-calculation.patch
mm-huge_memory-make-min_order_for_split-always-return-an-order.patch
mm-huge_memory-fix-folio-split-stats-counting.patch