FAILED: patch "[PATCH] mm/damon/tests/core-kunit: handle alloc failures on" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] mm/damon/tests/core-kunit: handle alloc failures on" failed to apply to 6.6-stable tree

[gregkh]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 3d443dd29a1db7efa587a4bb0c06a497e13ca9e4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026010518-overflow-headgear-2f02@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3d443dd29a1db7efa587a4bb0c06a497e13ca9e4 Mon Sep 17 00:00:00 2001
From: SeongJae Park <sj@kernel.org>
Date: Sat, 1 Nov 2025 11:20:00 -0700
Subject: [PATCH] mm/damon/tests/core-kunit: handle alloc failures on
 damon_test_merge_two()

damon_test_merge_two() is assuming all dynamic memory allocation in it
will succeed.  Those are indeed likely in the real use cases since those
allocations are too small to fail, but theoretically those could fail.  In
the case, inappropriate memory access can happen.  Fix it by appropriately
cleanup pre-allocated memory and skip the execution of the remaining tests
in the failure cases.

Link: https://lkml.kernel.org/r/20251101182021.74868-7-sj@kernel.org
Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index f5f3152cb8df..e8219fd23318 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -188,11 +188,21 @@ static void damon_test_merge_two(struct kunit *test)
 	int i;
 
 	t = damon_new_target();
+	if (!t)
+		kunit_skip(test, "target alloc fail");
 	r = damon_new_region(0, 100);
+	if (!r) {
+		damon_free_target(t);
+		kunit_skip(test, "region alloc fail");
+	}
 	r->nr_accesses = 10;
 	r->nr_accesses_bp = 100000;
 	damon_add_region(r, t);
 	r2 = damon_new_region(100, 300);
+	if (!r2) {
+		damon_free_target(t);
+		kunit_skip(test, "second region alloc fail");
+	}
 	r2->nr_accesses = 20;
 	r2->nr_accesses_bp = 200000;
 	damon_add_region(r2, t);

[PATCH 6.6.y] mm/damon/tests/core-kunit: handle alloc failures on damon_test_merge_two()

[SeongJae Park]

damon_test_merge_two() is assuming all dynamic memory allocation in it
will succeed.  Those are indeed likely in the real use cases since those
allocations are too small to fail, but theoretically those could fail.  In
the case, inappropriate memory access can happen.  Fix it by appropriately
cleanup pre-allocated memory and skip the execution of the remaining tests
in the failure cases.

Link: https://lkml.kernel.org/r/20251101182021.74868-7-sj@kernel.org
Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 3d443dd29a1db7efa587a4bb0c06a497e13ca9e4)
---
 mm/damon/core-test.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index 6cc8b245586d..c20f6bd11f36 100644
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -145,10 +145,20 @@ static void damon_test_merge_two(struct kunit *test)
 	int i;
 
 	t = damon_new_target();
+	if (!t)
+		kunit_skip(test, "target alloc fail");
 	r = damon_new_region(0, 100);
+	if (!r) {
+		damon_free_target(t);
+		kunit_skip(test, "region alloc fail");
+	}
 	r->nr_accesses = 10;
 	damon_add_region(r, t);
 	r2 = damon_new_region(100, 300);
+	if (!r2) {
+		damon_free_target(t);
+		kunit_skip(test, "second region alloc fail");
+	}
 	r2->nr_accesses = 20;
 	damon_add_region(r2, t);
 
-- 
2.47.3