The patch titled Subject: mm/damon/paddr: fix missing folio_put() has been added to the -mm mm-unstable branch. Its filename is mm-damon-paddr-fix-missing-folio_put.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: "andrew.yang" andrew.yang@mediatek.com Subject: mm/damon/paddr: fix missing folio_put() Date: Wed, 22 Feb 2023 14:42:20 +0800

damon_get_folio() would always increase folio _refcount and folio_isolate_lru() would increase folio _refcount if the folio's lru flag is set.

If an unevictable folio isolated successfully, there will be two more _refcount. The one from folio_isolate_lru() will be decreased in folio_puback_lru(), but the other one from damon_get_folio() will be left behind. This causes a pin page.

Whatever the case, the _refcount from damon_get_folio() should be decreased.

Link: https://lkml.kernel.org/r/20230222064223.6735-1-andrew.yang@mediatek.com Fixes: 57223ac29584 ("mm/damon/paddr: support the pageout scheme") Signed-off-by: andrew.yang andrew.yang@mediatek.com Reviewed-by: SeongJae Park sj@kernel.org Cc: stable@vger.kernel.org [5.16.x] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/damon/paddr.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)

--- a/mm/damon/paddr.c~mm-damon-paddr-fix-missing-folio_put +++ a/mm/damon/paddr.c @@ -250,12 +250,11 @@ static unsigned long damon_pa_pageout(st folio_put(folio); continue; } - if (folio_test_unevictable(folio)) { + if (folio_test_unevictable(folio)) folio_putback_lru(folio); - } else { + else list_add(&folio->lru, &folio_list); - folio_put(folio); - } + folio_put(folio); } applied = reclaim_pages(&folio_list); cond_resched(); _

Patches currently in -mm which might be from andrew.yang@mediatek.com are

mm-damon-paddr-fix-missing-folio_put.patch