From: liyouhong Date: Sun, 26 Jul 2026 01:48:15 +0000 (+0800) Subject: mm/damon/ops-common: putback folios on invalid migrate nid X-Git-Tag: v7.2-rc7~22^2~1 X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=5deb65c34e682e7c5f5df417a70e223e8fcc5f5a;p=thirdparty%2Fkernel%2Flinux.git mm/damon/ops-common: putback folios on invalid migrate nid damon_pa_migrate() and damos_va_migrate() isolate folios into a local list and then call damon_migrate_pages(). When target_nid is invalid (including the scheme default NUMA_NO_NODE / -1), damon_migrate_pages() returns early without putting the folios back to the LRU. Callers then discard the list head while those folios remain isolated with an extra reference taken by folio_isolate_lru(). The pages stay off the LRU for as long as the mapping exists (anon active+inactive counts drop while RSS does not), and the leftover references can pin the pages after the mapping is gone. Put the folios back on the invalid-nid path so ignored migration requests still return them to the LRU. Link: https://lore.kernel.org/20260726014815.1280757-1-dayou5941@163.com Fixes: 7e6c3130690a ("mm/damon/ops-common: ignore migration request to invalid nodes") Assisted-by: Cursor:grok-4.5 Reviewed-by: SJ Park Signed-off-by: liyouhong Cc: Signed-off-by: Andrew Morton --- diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c index 6bdd1cfd3863..9c178c175832 100644 --- a/mm/damon/ops-common.c +++ b/mm/damon/ops-common.c @@ -392,8 +392,15 @@ unsigned long damon_migrate_pages(struct list_head *folio_list, int target_nid) return nr_migrated; if (target_nid < 0 || target_nid >= MAX_NUMNODES || - !node_state(target_nid, N_MEMORY)) + !node_state(target_nid, N_MEMORY)) { + while (!list_empty(folio_list)) { + struct folio *folio = lru_to_folio(folio_list); + + list_del(&folio->lru); + folio_putback_lru(folio); + } return nr_migrated; + } noreclaim_flag = memalloc_noreclaim_save();