6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chris Li chrisl@kernel.org
commit 0885ef4705607936fc36a38fd74356e1c465b023 upstream.
I found a regression on mm-unstable during my swap stress test, using tmpfs to compile linux. The test OOM very soon after the make spawns many cc processes.
It bisects down to this change: 33dfe9204f29b415bbc0abb1a50642d1ba94f5e9 (mm/gup: clear the LRU flag of a page before adding to LRU batch)
Yu Zhao propose the fix: "I think this is one of the potential side effects -- Huge mentioned earlier about isolate_lru_folios():"
I test that with it the swap stress test no longer OOM.
Link: https://lore.kernel.org/r/CAOUHufYi9h0kz5uW3LHHS3ZrVwEq-kKp8S6N-MZUmErNAXoXm... Link: https://lkml.kernel.org/r/20240905-lru-flag-v2-1-8a2d9046c594@kernel.org Fixes: 33dfe9204f29 ("mm/gup: clear the LRU flag of a page before adding to LRU batch") Signed-off-by: Chris Li chrisl@kernel.org Suggested-by: Yu Zhao yuzhao@google.com Suggested-by: Hugh Dickins hughd@google.com Closes: https://lore.kernel.org/all/CAF8kJuNP5iTj2p07QgHSGOJsiUfYpJ2f4R1Q5-3BN9JiD9W... Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4300,7 +4300,7 @@ static bool sort_folio(struct lruvec *lr }
/* ineligible */ - if (zone > sc->reclaim_idx) { + if (!folio_test_lru(folio) || zone > sc->reclaim_idx) { gen = folio_inc_gen(lruvec, folio, false); list_move_tail(&folio->lru, &lrugen->folios[gen][type][zone]); return true;