mm/khugepaged: fix the address passed to notifier on testing young

commit 394bfac1c7f7b701c2c93834c5761b9c9ceeebcf upstream.

Commit 8ee5382 ("thp: mmu_notifier_test_young") introduced
mmu_notifier_test_young(), but we are passing the wrong address.
In xxx_scan_pmd(), the actual iteration address is "_address" not
"address".  We seem to misuse the variable on the very beginning.

Change it to the right one.

[akpm@linux-foundation.org fix whitespace, per everyone]
Link: https://lkml.kernel.org/r/20250822063318.11644-1-richard.weiyang@gmail.com
Fixes: 8ee5382 ("thp: mmu_notifier_test_young")
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Barry Song <baohua@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>

Author: RichardWeiYang

mm/khugepaged.c

@@ -1224,7 +1224,7 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
 		}
 		if (pte_young(pteval) ||
 		    page_is_young(page) || PageReferenced(page) ||
-		    mmu_notifier_test_young(vma->vm_mm, address))
+		    mmu_notifier_test_young(vma->vm_mm, _address))
 			referenced++;
 	}
 	if (writable) {