--- a/mm/migrate.c~mm-migratec-migrate-pg_readahead-flag +++ a/mm/migrate.c @@ -647,6 +647,14 @@ void migrate_page_states(struct page *ne if (PageWriteback(newpage)) end_page_writeback(newpage); + /* + * PG_readahead shares the same bit with PG_reclaim. The above + * end_page_writeback() may clear PG_readahead mistakenly, so set the + * bit after that. + */ + if (PageReadahead(page)) + SetPageReadahead(newpage); + copy_page_owner(page, newpage); mem_cgroup_migrate(page, newpage);