* [PATCH 6.16.y] mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters()
[not found] <2025091327-cyclist-impeach-ca7c@gregkh>
@ 2025-09-14 3:11 ` SeongJae Park
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From: SeongJae Park @ 2025-09-14 3:11 UTC (permalink / raw)
To: stable
Cc: damon, Quanmin Yan, SeongJae Park, Kefeng Wang, ze zuo,
Andrew Morton
From: Quanmin Yan <yanquanmin1@huawei.com>
When creating a new scheme of DAMON_RECLAIM, the calculation of
'min_age_region' uses 'aggr_interval' as the divisor, which may lead to
division-by-zero errors. Fix it by directly returning -EINVAL when such a
case occurs.
Link: https://lkml.kernel.org/r/20250827115858.1186261-3-yanquanmin1@huawei.com
Fixes: f5a79d7c0c87 ("mm/damon: introduce struct damos_access_pattern")
Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: ze zuo <zuoze1@huawei.com>
Cc: <stable@vger.kernel.org> [6.1+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit e6b543ca9806d7bced863f43020e016ee996c057)
Signed-off-by: SeongJae Park <sj@kernel.org>
---
mm/damon/reclaim.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index a675150965e0..ade3ff724b24 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -194,6 +194,11 @@ static int damon_reclaim_apply_parameters(void)
if (err)
return err;
+ if (!damon_reclaim_mon_attrs.aggr_interval) {
+ err = -EINVAL;
+ goto out;
+ }
+
err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
if (err)
goto out;
--
2.39.5
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