From 6dbb3c2e90202f5f35dd18e64e0070a465739610 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 11 Mar 2024 19:18:34 +0000 Subject: [PATCH] BACKPORT: mm: remove folio from deferred split list before uncharging it When freeing a large folio, we must remove it from the deferred split list before we uncharge it as each memcg has its own deferred split list (with associated lock) and removing a folio from the deferred split list while holding the wrong lock will corrupt that list and cause various related problems. Link: https://lore.kernel.org/linux-mm/367a14f7-340e-4b29-90ae-bc3fcefdd5f4@arm.com/ Link: https://lkml.kernel.org/r/20240311191835.312162-1-willy@infradead.org Fixes: f77171d241e3 (mm: allow non-hugetlb large folios to be batch processed) Fixes: 29f3843026cf (mm: free folios directly in move_folios_to_lru()) Fixes: bc2ff4cbc329 (mm: free folios in a batch in shrink_folio_list()) Change-Id: I012dfb4c33678bb1e8a546a6dc78a0227858aa5b Signed-off-by: Matthew Wilcox (Oracle) Debugged-by: Ryan Roberts Tested-by: Ryan Roberts Signed-off-by: Andrew Morton (cherry picked from commit 47932e7048df9156e96133ee90fb3e9df68dbd15) [ Drop changes to shrink_folio_list() and move_folios_to_lru() in mm/vmscan.c since they both call destroy_large_folio() which removes the folio from the deferred split list - Kalesh Singh ] [ Use folio_unqueue_deferred_split() instead of folio_undo_large_unmappable(); which also performs the necessary large folio checks - Kalesh Singh ] Bug: 419599659 Signed-off-by: Kalesh Singh --- mm/swap.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/swap.c b/mm/swap.c index 0fba8649eb3d..174259a9a5f7 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -1019,6 +1019,7 @@ void folios_put_refs(struct folio_batch *folios, unsigned int *refs) continue; } + folio_unqueue_deferred_split(folio); __page_cache_release(folio, &lruvec, &flags); if (j != i)