The patch titled Subject: mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters() has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-damon-reclaim-avoid-divide-by-zero-in-damon_reclaim_apply_parameters.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Quanmin Yan yanquanmin1@huawei.com Subject: mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters() Date: Wed, 27 Aug 2025 19:58:58 +0800

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 ---

mm/damon/reclaim.c | 5 +++++ 1 file changed, 5 insertions(+)

--- a/mm/damon/reclaim.c~mm-damon-reclaim-avoid-divide-by-zero-in-damon_reclaim_apply_parameters +++ a/mm/damon/reclaim.c @@ -194,6 +194,11 @@ static int damon_reclaim_apply_parameter if (err) return err;

+ if (!damon_reclaim_mon_attrs.aggr_interval) { + err = -EINVAL; + goto out; + } + err = damon_set_attrs(param_ctx, &damon_reclaim_mon_attrs); if (err) goto out; _

Patches currently in -mm which might be from yanquanmin1@huawei.com are

mm-damon-core-prevent-unnecessary-overflow-in-damos_set_effective_quota.patch mm-damon-lru_sort-avoid-divide-by-zero-in-damon_lru_sort_apply_parameters.patch mm-damon-reclaim-avoid-divide-by-zero-in-damon_reclaim_apply_parameters.patch