The patch titled
Subject: mm/damon/core-test: test max_nr_accesses overflow caused divide-by-zero
has been added to the -mm mm-unstable branch. Its filename is
mm-damon-core-test-test-max_nr_accesses-overflow-caused-divide-by-zero.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-test-test-max_nr_accesses-overflow-caused-divide-by-zero.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: SeongJae Park <sj@xxxxxxxxxx>
Subject: mm/damon/core-test: test max_nr_accesses overflow caused divide-by-zero
Date: Wed, 13 Dec 2023 19:03:34 +0000
Commit 35f5d94187a6 ("mm/damon: implement a function for max nr_accesses
safe calculation") has fixed an overflow bug that could cause
divide-by-zero. Add a kunit test for the bug to ensure similar bugs are
not introduced again.
Link: https://lkml.kernel.org/r/20231213190338.54146-3-sj@xxxxxxxxxx
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/damon/core-test.h | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/mm/damon/core-test.h~mm-damon-core-test-test-max_nr_accesses-overflow-caused-divide-by-zero
+++ a/mm/damon/core-test.h
@@ -302,6 +302,16 @@ static void damon_test_set_regions(struc
damon_destroy_target(t);
}
+static void damon_test_nr_accesses_to_accesses_bp(struct kunit *test)
+{
+ struct damon_attrs attrs = {
+ .sample_interval = 10,
+ .aggr_interval = ((unsigned long)UINT_MAX + 1) * 10
+ };
+
+ KUNIT_EXPECT_EQ(test, damon_nr_accesses_to_accesses_bp(123, &attrs), 0);
+}
+
static void damon_test_update_monitoring_result(struct kunit *test)
{
struct damon_attrs old_attrs = {
@@ -487,6 +497,7 @@ static struct kunit_case damon_test_case
KUNIT_CASE(damon_test_split_regions_of),
KUNIT_CASE(damon_test_ops_registration),
KUNIT_CASE(damon_test_set_regions),
+ KUNIT_CASE(damon_test_nr_accesses_to_accesses_bp),
KUNIT_CASE(damon_test_update_monitoring_result),
KUNIT_CASE(damon_test_set_attrs),
KUNIT_CASE(damon_test_moving_sum),
_
Patches currently in -mm which might be from sj@xxxxxxxxxx are
selftests-damon-implement-a-python-module-for-test-purpose-damon-sysfs-controls.patch
selftests-damon-_damon_sysfs-implement-kdamonds-start-function.patch
selftests-damon-_damon_sysfs-implement-updat_schemes_tried_bytes-command.patch
selftests-damon-add-a-test-for-update_schemes_tried_regions-sysfs-command.patch
selftests-damon-add-a-test-for-update_schemes_tried_regions-hang-bug.patch
mm-damon-update-email-of-seongjae.patch
mm-damon-core-test-test-max_nr_accesses-overflow-caused-divide-by-zero.patch
docs-mm-damon-design-place-execution-model-and-data-structures-at-the-beginning.patch
docs-admin-guide-mm-damon-usage-update-context-directory-section-label.patch
docs-admin-guide-mm-damon-usage-add-links-to-sysfs-files-hierarchy.patch
docs-admin-guide-mm-damon-usage-use-a-list-for-state-sysfs-file-input-commands.patch
