When calculating the hotness threshold for lru_prio scheme of
DAMON_LRU_SORT, the module divides some values by the maximum
nr_accesses. However, due to the type of the related variables, simple
division-based calculation of the divisor can return zero. As a result,
divide-by-zero is possible. Fix it by using damon_max_nr_accesses(),
which handles the case.
Reported-by: Jakub Acs <acsjakub@xxxxxxxxx>
Fixes: 40e983cca927 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Cc: <stable@xxxxxxxxxxxxxxx> # 6.0.x
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/lru_sort.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index 3ecdcc029443..f2e5f9431892 100644
--- a/mm/damon/lru_sort.c
+++ b/mm/damon/lru_sort.c
@@ -195,9 +195,7 @@ static int damon_lru_sort_apply_parameters(void)
if (err)
return err;
- /* aggr_interval / sample_interval is the maximum nr_accesses */
- hot_thres = damon_lru_sort_mon_attrs.aggr_interval /
- damon_lru_sort_mon_attrs.sample_interval *
+ hot_thres = damon_max_nr_accesses(&damon_lru_sort_mon_attrs) *
hot_thres_access_freq / 1000;
scheme = damon_lru_sort_new_hot_scheme(hot_thres);
if (!scheme)
--
2.34.1
