From:   SeongJae Park <sj@kernel.org>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     SeongJae Park <sj@kernel.org>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        "Vishal Moola (Oracle)" <vishal.moola@gmail.com>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        damon@lists.linux.dev, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: [PATCH 2/2] mm/damon/paddr: fix folio_nr_pages() after folio_put() in damon_pa_mark_accessed_or_deactivate()
Date:   Sat,  4 Mar 2023 19:39:49 +0000
Message-Id: <20230304193949.296391-3-sj@kernel.org>
In-Reply-To: <20230304193949.296391-1-sj@kernel.org>
References: <20230304193949.296391-1-sj@kernel.org>
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damon_pa_mark_accessed_or_deactivate() is accessing a folio via
folio_nr_pages() after folio_put() for the folio has invoked.  Fix it.

Fixes: f70da5ee8fe1 ("mm/damon: convert damon_pa_mark_accessed_or_deactivate() to use folios")
Cc: <stable@vger.kernel.org> # 6.3.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/paddr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 10f159b315ea..0db724aec5cb 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -277,8 +277,8 @@ static inline unsigned long damon_pa_mark_accessed_or_deactivate(
 			folio_mark_accessed(folio);
 		else
 			folio_deactivate(folio);
-		folio_put(folio);
 		applied += folio_nr_pages(folio);
+		folio_put(folio);
 	}
 	return applied * PAGE_SIZE;
 }
-- 
2.25.1