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charset="utf-8" Pagecache uses multi-index entries for large folio, so does shmem. Only swap cache still stores multiple entries for a single large folio. Commit fc346d0a70a1 ("mm: migrate high-order folios in swap cache correctly= ") fixed swap cache but got shmem wrong by storing multiple entries for a large shmem folio. Fix it by storing a single entry for a shmem folio. Fixes: fc346d0a70a1 ("mm: migrate high-order folios in swap cache correctly= ") Reported-by: Liu Shixin Closes: https://lore.kernel.org/all/28546fb4-5210-bf75-16d6-43e1f8646080@hu= awei.com/ Signed-off-by: Zi Yan Reviewed-by: Shivank Garg Reviewed-by: Baolin Wang --- mm/migrate.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/migrate.c b/mm/migrate.c index 365c6daa8d1b..2c9669135a38 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -524,7 +524,11 @@ static int __folio_migrate_mapping(struct address_spac= e *mapping, folio_set_swapcache(newfolio); newfolio->private =3D folio_get_private(folio); } - entries =3D nr; + /* shmem uses high-order entry */ + if (!folio_test_anon(folio)) + entries =3D 1; + else + entries =3D nr; } else { VM_BUG_ON_FOLIO(folio_test_swapcache(folio), folio); entries =3D 1; --=20 2.47.2