diff options
Diffstat (limited to 'mm/migrate.c')
-rw-r--r-- | mm/migrate.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 3b676b0..c387786 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1679,9 +1679,21 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm, page_xchg_last_nid(new_page, page_last_nid(page)); isolated = numamigrate_isolate_page(pgdat, page); - if (!isolated) { + + /* + * Failing to isolate or a GUP pin prevents migration. The expected + * page count is 2. 1 for anonymous pages without a mapping and 1 + * for the callers pin. If the page was isolated, the page will + * need to be put back on the LRU. + */ + if (!isolated || page_count(page) != 2) { count_vm_events(PGMIGRATE_FAIL, HPAGE_PMD_NR); put_page(new_page); + if (isolated) { + putback_lru_page(page); + isolated = 0; + goto out; + } goto out_keep_locked; } |