Re: [PATCH 1/1] mm/migrate: fix list corruption in migration of non-LRU movable pages
From: Michal Hocko
Date: Wed Sep 04 2019 - 02:38:40 EST
On Wed 04-09-19 02:18:38, sunqiuyang wrote:
> The isolate path of non-lru movable pages:
> // if PageIsolated, goto out_no_isolated
> list_add(&page->lru, &cc->migratepages)
> The migration path:
> /* here, the page could be isolated again by another thread, and added into another cc->migratepages,
> since PG_Isolated has been cleared, and not protected by page_lock */
But the page has been migrated already and not freed yet because there
is still a pin on it. So nobody should be touching it at this stage.
Or do I still miss something?