This is a note to let you know that I've just added the patch titled
mm/damon/paddr: fix missing folio_put()
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-damon-paddr-fix-missing-folio_put.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3f98c9a62c338bbe06a215c9491e6166ea39bf82 Mon Sep 17 00:00:00 2001
From: "andrew.yang" <andrew.yang@xxxxxxxxxxxx>
Date: Wed, 22 Feb 2023 14:42:20 +0800
Subject: mm/damon/paddr: fix missing folio_put()
From: andrew.yang <andrew.yang@xxxxxxxxxxxx>
commit 3f98c9a62c338bbe06a215c9491e6166ea39bf82 upstream.
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@xxxxxxxxxxxx
Fixes: 57223ac29584 ("mm/damon/paddr: support the pageout scheme")
Signed-off-by: andrew.yang <andrew.yang@xxxxxxxxxxxx>
Reviewed-by: SeongJae Park <sj@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [5.16.x]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/damon/paddr.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -219,12 +219,11 @@ static unsigned long damon_pa_pageout(st
put_page(page);
continue;
}
- if (PageUnevictable(page)) {
+ if (PageUnevictable(page))
putback_lru_page(page);
- } else {
+ else
list_add(&page->lru, &page_list);
- put_page(page);
- }
+ put_page(page);
}
applied = reclaim_pages(&page_list);
cond_resched();
Patches currently in stable-queue which might be from andrew.yang@xxxxxxxxxxxx are
queue-6.2/mm-damon-paddr-fix-missing-folio_put.patch
