The D-cache maintenance inside move_to_new_page() only consider one page,
there is still D-cache maintenance issue for tail pages of THP. Fix this
by not using flush_dcache_folio() since it is not backportable.
Fixes: 616b8371539a ("mm: thp: enable thp migration in generic path")
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
Changes in v2:
- Using a for loop instead of the folio variant for backportable.
mm/migrate.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/mm/migrate.c b/mm/migrate.c
index c9296d63878d..c418e8d92b9c 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -933,9 +933,12 @@ static int move_to_new_page(struct page *newpage, struct page *page,
if (!PageMappingFlags(page))
page->mapping = NULL;
- if (likely(!is_zone_device_page(newpage)))
- flush_dcache_page(newpage);
+ if (likely(!is_zone_device_page(newpage))) {
+ int i, nr = compound_nr(newpage);
+ for (i = 0; i < nr; i++)
+ flush_dcache_page(newpage + i);
+ }
}
out:
return rc;
--
2.11.0
