This is a note to let you know that I've just added the patch titled list: test: Add a test for list_is_head() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: list-test-add-a-test-for-list_is_head.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 37dc573c0a547e1aed0c9abb480fab797bd3833f Mon Sep 17 00:00:00 2001 From: David Gow <davidgow@xxxxxxxxxx> Date: Fri, 25 Feb 2022 10:52:48 +0800 Subject: list: test: Add a test for list_is_head() From: David Gow <davidgow@xxxxxxxxxx> commit 37dc573c0a547e1aed0c9abb480fab797bd3833f upstream. list_is_head() was added recently[1], and didn't have a KUnit test. The implementation is trivial, so it's not a particularly exciting test, but it'd be nice to get back to full coverage of the list functions. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/include/linux/list.h?id=0425473037db40d9e322631f2d4dc6ef51f97e88 Signed-off-by: David Gow <davidgow@xxxxxxxxxx> Acked-by: Daniel Latypov <dlatypov@xxxxxxxxxx> Acked-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- lib/list-test.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/lib/list-test.c +++ b/lib/list-test.c @@ -234,6 +234,24 @@ static void list_test_list_bulk_move_tai KUNIT_EXPECT_EQ(test, i, 2); } +static void list_test_list_is_head(struct kunit *test) +{ + struct list_head a, b, c; + + /* Two lists: [a] -> b, [c] */ + INIT_LIST_HEAD(&a); + INIT_LIST_HEAD(&c); + list_add_tail(&b, &a); + + KUNIT_EXPECT_TRUE_MSG(test, list_is_head(&a, &a), + "Head element of same list"); + KUNIT_EXPECT_FALSE_MSG(test, list_is_head(&a, &b), + "Non-head element of same list"); + KUNIT_EXPECT_FALSE_MSG(test, list_is_head(&a, &c), + "Head element of different list"); +} + + static void list_test_list_is_first(struct kunit *test) { struct list_head a, b; @@ -710,6 +728,7 @@ static struct kunit_case list_test_cases KUNIT_CASE(list_test_list_move), KUNIT_CASE(list_test_list_move_tail), KUNIT_CASE(list_test_list_bulk_move_tail), + KUNIT_CASE(list_test_list_is_head), KUNIT_CASE(list_test_list_is_first), KUNIT_CASE(list_test_list_is_last), KUNIT_CASE(list_test_list_empty), Patches currently in stable-queue which might be from davidgow@xxxxxxxxxx are queue-5.15/list-test-add-a-test-for-list_is_head.patch