From: Hugh Dickins <hughd@xxxxxxxxxx>
[ Upstream commit 2f33a706027c94cd4f70fcd3e3f4a17c1ce4ea4b ]
When collapse_file() calls try_to_release_page(), it has already isolated
the page: so if releasing buffers happens to fail (as it sometimes does),
remember to putback_lru_page(): otherwise that page is left unreclaimable
and unfreeable, and the file extent uncollapsible.
Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS")
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [5.4+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2005231837500.1766@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
mm/khugepaged.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index b679908743cb..ba059e68cf50 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1673,6 +1673,7 @@ static void collapse_file(struct mm_struct *mm,
if (page_has_private(page) &&
!try_to_release_page(page, GFP_KERNEL)) {
result = SCAN_PAGE_HAS_PRIVATE;
+ putback_lru_page(page);
goto out_unlock;
}
--
2.25.1
