From: Josh Law <objecting@objecting.org>
To: sj@kernel.org, akpm@linux-foundation.org
Cc: damon@lists.linux.dev, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, Josh Law <objecting@objecting.org>
Subject: [PATCH 2/2] mm/damon/reclaim: fix min_age_region truncation from unsigned long to unsigned int
Date: Thu, 19 Mar 2026 16:16:20 +0000 [thread overview]
Message-ID: <20260319161620.189392-3-objecting@objecting.org> (raw)
In-Reply-To: <20260319161620.189392-1-objecting@objecting.org>
min_age / aggr_interval can exceed UINT_MAX with extreme but valid
module parameter values, silently truncating min_age_region and
lowering the cold-page age threshold below what the user intended.
Clamp the result to UINT_MAX to match the field's type.
Signed-off-by: Josh Law <objecting@objecting.org>
---
mm/damon/reclaim.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 9b55df304e51..303c64a56073 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -170,8 +170,8 @@ static struct damos *damon_reclaim_new_scheme(void)
.min_nr_accesses = 0,
.max_nr_accesses = 0,
/* for min_age or more micro-seconds */
- .min_age_region = min_age /
- damon_reclaim_mon_attrs.aggr_interval,
+ .min_age_region = min_t(unsigned long, min_age /
+ damon_reclaim_mon_attrs.aggr_interval, UINT_MAX),
.max_age_region = UINT_MAX,
};
--
2.34.1
next prev parent reply other threads:[~2026-03-19 16:16 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-19 16:16 [PATCH 0/2] mm/damon/reclaim: fix addr_unit validation and age truncation Josh Law
2026-03-19 16:16 ` [PATCH 1/2] mm/damon/reclaim: reject non-power-of-2 addr_unit Josh Law
2026-03-20 2:29 ` SeongJae Park
2026-03-19 16:16 ` Josh Law [this message]
2026-03-20 2:48 ` [PATCH 2/2] mm/damon/reclaim: fix min_age_region truncation from unsigned long to unsigned int SeongJae Park
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