[merged mm-stable] mm-damon-lru_sort-avoid-divide-by-zero-in-hot-threshold-calculation.patch removed from -mm tree

[merged mm-stable] mm-damon-lru_sort-avoid-divide-by-zero-in-hot-threshold-calculation.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/damon/lru_sort: avoid divide-by-zero in hot threshold calculation
has been removed from the -mm tree.  Its filename was
     mm-damon-lru_sort-avoid-divide-by-zero-in-hot-threshold-calculation.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/lru_sort: avoid divide-by-zero in hot threshold calculation
Date: Thu, 19 Oct 2023 19:49:23 +0000

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.

Link: https://lkml.kernel.org/r/20231019194924.100347-5-sj@kernel.org
Fixes: 40e983cca927 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: Jakub Acs <acsjakub@amazon.de>
Cc: <stable@vger.kernel.org>	[6.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/lru_sort.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/mm/damon/lru_sort.c~mm-damon-lru_sort-avoid-divide-by-zero-in-hot-threshold-calculation
+++ a/mm/damon/lru_sort.c
@@ -195,9 +195,7 @@ static int damon_lru_sort_apply_paramete
 	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)
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-sysfs-remove-requested-targets-when-online-commit-inputs.patch