Re: [PATCH] lib: overflow: Convert to Kunit

From: Daniel Latypov
Date: Wed Feb 16 2022 - 17:57:31 EST


On Wed, Feb 16, 2022 at 2:42 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> Convert overflow unit tests to KUnit, for better integration into the
> kernel self test framework. Includes a rename of test_overflow.c to
> overflow_kunit.c, and CONFIG_TEST_OVERFLOW to CONFIG_OVERFLOW_KUNIT_TEST.
>
> $ ./tools/testing/kunit/kunit.py config
> ...
> $ ./tools/testing/kunit/kunit.py run overflow

JFYI, you can run this as a one-liner via

$ ./tools/testing/kunit/kunit.py run --kunitconfig /dev/stdin <<EOF
CONFIG_KUNIT=y
CONFIG_TEST_OVERFLOW=y
EOF

The above is taken from my own duplicate version of this patch
[1] https://lore.kernel.org/linux-kselftest/20210503211536.1384578-1-dlatypov@xxxxxxxxxx/

> ...
> [14:33:51] Starting KUnit Kernel (1/1)...
> [14:33:51] ============================================================
> [14:33:51] ================== overflow (11 subtests) ==================
> [14:33:51] [PASSED] u8_overflow_test
> [14:33:51] [PASSED] s8_overflow_test
> [14:33:51] [PASSED] u16_overflow_test
> [14:33:51] [PASSED] s16_overflow_test
> [14:33:51] [PASSED] u32_overflow_test
> [14:33:51] [PASSED] s32_overflow_test
> [14:33:51] [PASSED] u64_overflow_test
> [14:33:51] [PASSED] s64_overflow_test
> [14:33:51] [PASSED] overflow_shift_test
> [14:33:51] [PASSED] overflow_allocation_test
> [14:33:51] [PASSED] overflow_size_helpers_test
> [14:33:51] ==================== [PASSED] overflow =====================
> [14:33:51] ============================================================
> [14:33:51] Testing complete. Passed: 11, Failed: 0, Crashed: 0, Skipped: 0, Errors: 0
> [14:33:51] Elapsed time: 12.525s total, 0.001s configuring, 12.402s building, 0.101s running
>
> Cc: David Gow <davidgow@xxxxxxxxxx>
> Cc: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> Co-developed-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Signed-off-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Link: https://lore.kernel.org/lkml/20200720224418.200495-1-vitor@xxxxxxxxxxx/
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Daniel Latypov <dlatypov@xxxxxxxxxx>

Looks good to me, some minor nits/suggestions wrt KUnit usage.
Nice to see this test converted over!

> ---
> Assuming no one objects, I'll carry this in my for-next/overflow tree. :)
> ---
> lib/Kconfig.debug | 16 +-
> lib/Makefile | 2 +-
> lib/{test_overflow.c => overflow_kunit.c} | 562 ++++++++++------------
> 3 files changed, 270 insertions(+), 310 deletions(-)
> rename lib/{test_overflow.c => overflow_kunit.c} (54%)
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 14b89aa37c5c..14d90d03bc8d 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2214,9 +2214,6 @@ config TEST_UUID
> config TEST_XARRAY
> tristate "Test the XArray code at runtime"
>
> -config TEST_OVERFLOW
> - tristate "Test check_*_overflow() functions at runtime"
> -
> config TEST_RHASHTABLE
> tristate "Perform selftest on resizable hash table"
> help
> @@ -2501,6 +2498,19 @@ config MEMCPY_KUNIT_TEST
>
> If unsure, say N.
>
> +config OVERFLOW_KUNIT_TEST
> + tristate "Test check_*_overflow() functions at runtime" if !KUNIT_ALL_TESTS
> + depends on KUNIT
> + default KUNIT_ALL_TESTS
> + help
> + Builds unit tests for the check_*_overflow(), size_*(), allocation, and
> + related functions.
> +
> + For more information on KUnit and unit tests in general please refer
> + to the KUnit documentation in Documentation/dev-tools/kunit/.
> +
> + If unsure, say N.
> +
> config TEST_UDELAY
> tristate "udelay test driver"
> help
> diff --git a/lib/Makefile b/lib/Makefile
> index 300f569c626b..fdfcbfaff32f 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -77,7 +77,6 @@ obj-$(CONFIG_TEST_LIST_SORT) += test_list_sort.o
> obj-$(CONFIG_TEST_MIN_HEAP) += test_min_heap.o
> obj-$(CONFIG_TEST_LKM) += test_module.o
> obj-$(CONFIG_TEST_VMALLOC) += test_vmalloc.o
> -obj-$(CONFIG_TEST_OVERFLOW) += test_overflow.o
> obj-$(CONFIG_TEST_RHASHTABLE) += test_rhashtable.o
> obj-$(CONFIG_TEST_SORT) += test_sort.o
> obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
> @@ -363,6 +362,7 @@ obj-$(CONFIG_BITS_TEST) += test_bits.o
> obj-$(CONFIG_CMDLINE_KUNIT_TEST) += cmdline_kunit.o
> obj-$(CONFIG_SLUB_KUNIT_TEST) += slub_kunit.o
> obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o
> +obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow_kunit.o
>
> obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
>
> diff --git a/lib/test_overflow.c b/lib/overflow_kunit.c
> similarity index 54%
> rename from lib/test_overflow.c
> rename to lib/overflow_kunit.c
> index f6530fce799d..4cc27b9926a1 100644
> --- a/lib/test_overflow.c
> +++ b/lib/overflow_kunit.c
> @@ -1,9 +1,13 @@
> // SPDX-License-Identifier: GPL-2.0 OR MIT
> /*
> - * Test cases for arithmetic overflow checks.
> + * Test cases for arithmetic overflow checks. See:
> + * https://www.kernel.org/doc/html/latest/dev-tools/kunit/kunit-tool.html#configuring-building-and-running-tests
> + * ./tools/testing/kunit/kunit.py config
> + * ./tools/testing/kunit/kunit.py run overflow [--raw_output]
> */
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

We can drop the pr_fmt now, I think

>
> +#include <kunit/test.h>
> #include <linux/device.h>
> #include <linux/init.h>
> #include <linux/kernel.h>
> @@ -19,7 +23,7 @@
> t a, b; \
> t sum, diff, prod; \
> bool s_of, d_of, p_of; \
> - } t ## _tests[] __initconst
> + } t ## _tests[]
>
> DEFINE_TEST_ARRAY(u8) = {
> {0, 0, 0, 0, 0, false, false, false},
> @@ -220,43 +224,31 @@ DEFINE_TEST_ARRAY(s64) = {
> bool _of; \
> \
> _of = check_ ## op ## _overflow(a, b, &_r); \
> - if (_of != of) { \
> - pr_warn("expected "fmt" "sym" "fmt \
> - " to%s overflow (type %s)\n", \
> - a, b, of ? "" : " not", #t); \
> - err = 1; \
> - } \
> - if (_r != r) { \
> - pr_warn("expected "fmt" "sym" "fmt" == " \
> - fmt", got "fmt" (type %s)\n", \
> - a, b, r, _r, #t); \
> - err = 1; \
> - } \
> + KUNIT_EXPECT_EQ_MSG(test, _of, of, \
> + "expected "fmt" "sym" "fmt" to%s overflow (type %s)\n", \
> + a, b, of ? "" : " not", #t); \
> + KUNIT_EXPECT_EQ_MSG(test, _r, r, \
> + "expected "fmt" "sym" "fmt" == "fmt", got "fmt" (type %s)\n", \
> + a, b, r, _r, #t); \
> } while (0)
>
> #define DEFINE_TEST_FUNC(t, fmt) \
> -static int __init do_test_ ## t(const struct test_ ## t *p) \
> +static void do_test_ ## t(struct kunit *test, const struct test_ ## t *p) \
> { \
> - int err = 0; \
> - \
> check_one_op(t, fmt, add, "+", p->a, p->b, p->sum, p->s_of); \
> check_one_op(t, fmt, add, "+", p->b, p->a, p->sum, p->s_of); \
> check_one_op(t, fmt, sub, "-", p->a, p->b, p->diff, p->d_of); \
> check_one_op(t, fmt, mul, "*", p->a, p->b, p->prod, p->p_of); \
> check_one_op(t, fmt, mul, "*", p->b, p->a, p->prod, p->p_of); \
> - \
> - return err; \
> } \
> \
> -static int __init test_ ## t ## _overflow(void) { \
> - int err = 0; \
> +static void t ## _overflow_test(struct kunit *test) { \
> unsigned i; \
> \
> for (i = 0; i < ARRAY_SIZE(t ## _tests); ++i) \
> - err |= do_test_ ## t(&t ## _tests[i]); \
> - pr_info("%zu %s arithmetic tests finished\n", \
> + do_test_ ## t(test, &t ## _tests[i]); \
> + kunit_info(test, "%zu %s arithmetic tests finished\n", \
> ARRAY_SIZE(t ## _tests), #t); \
> - return err; \
> }
>
> DEFINE_TEST_FUNC(u8, "%d");
> @@ -270,198 +262,176 @@ DEFINE_TEST_FUNC(u64, "%llu");
> DEFINE_TEST_FUNC(s64, "%lld");
> #endif
>
> -static int __init test_overflow_calculation(void)
> -{
> - int err = 0;
> -
> - err |= test_u8_overflow();
> - err |= test_s8_overflow();
> - err |= test_u16_overflow();
> - err |= test_s16_overflow();
> - err |= test_u32_overflow();
> - err |= test_s32_overflow();
> -#if BITS_PER_LONG == 64
> - err |= test_u64_overflow();
> - err |= test_s64_overflow();
> -#endif
> -
> - return err;
> -}
> -
> -static int __init test_overflow_shift(void)
> +static void overflow_shift_test(struct kunit *test)
> {
> - int err = 0;
> int count = 0;
>
> /* Args are: value, shift, type, expected result, overflow expected */
> -#define TEST_ONE_SHIFT(a, s, t, expect, of) ({ \
> - int __failed = 0; \
> +#define TEST_ONE_SHIFT(a, s, t, expect, of) do { \
> typeof(a) __a = (a); \
> typeof(s) __s = (s); \
> t __e = (expect); \
> t __d; \
> bool __of = check_shl_overflow(__a, __s, &__d); \
> if (__of != of) { \
> - pr_warn("expected (%s)(%s << %s) to%s overflow\n", \
> + KUNIT_EXPECT_EQ_MSG(test, __of, of, \
> + "expected (%s)(%s << %s) to%s overflow\n", \
> #t, #a, #s, of ? "" : " not"); \
> - __failed = 1; \
> } else if (!__of && __d != __e) { \
> - pr_warn("expected (%s)(%s << %s) == %s\n", \
> + KUNIT_EXPECT_EQ_MSG(test, __d, __e, \
> + "expected (%s)(%s << %s) == %s\n", \
> #t, #a, #s, #expect); \
> if ((t)-1 < 0) \
> - pr_warn("got %lld\n", (s64)__d); \
> + kunit_info(test, "got %lld\n", (s64)__d); \
> else \
> - pr_warn("got %llu\n", (u64)__d); \
> - __failed = 1; \
> + kunit_info(test, "got %llu\n", (u64)__d); \
> } \
> count++; \
> - __failed; \
> -})
> +} while (0)
>
> /* Sane shifts. */
> - err |= TEST_ONE_SHIFT(1, 0, u8, 1 << 0, false);
> - err |= TEST_ONE_SHIFT(1, 4, u8, 1 << 4, false);
> - err |= TEST_ONE_SHIFT(1, 7, u8, 1 << 7, false);
> - err |= TEST_ONE_SHIFT(0xF, 4, u8, 0xF << 4, false);
> - err |= TEST_ONE_SHIFT(1, 0, u16, 1 << 0, false);
> - err |= TEST_ONE_SHIFT(1, 10, u16, 1 << 10, false);
> - err |= TEST_ONE_SHIFT(1, 15, u16, 1 << 15, false);
> - err |= TEST_ONE_SHIFT(0xFF, 8, u16, 0xFF << 8, false);
> - err |= TEST_ONE_SHIFT(1, 0, int, 1 << 0, false);
> - err |= TEST_ONE_SHIFT(1, 16, int, 1 << 16, false);
> - err |= TEST_ONE_SHIFT(1, 30, int, 1 << 30, false);
> - err |= TEST_ONE_SHIFT(1, 0, s32, 1 << 0, false);
> - err |= TEST_ONE_SHIFT(1, 16, s32, 1 << 16, false);
> - err |= TEST_ONE_SHIFT(1, 30, s32, 1 << 30, false);
> - err |= TEST_ONE_SHIFT(1, 0, unsigned int, 1U << 0, false);
> - err |= TEST_ONE_SHIFT(1, 20, unsigned int, 1U << 20, false);
> - err |= TEST_ONE_SHIFT(1, 31, unsigned int, 1U << 31, false);
> - err |= TEST_ONE_SHIFT(0xFFFFU, 16, unsigned int, 0xFFFFU << 16, false);
> - err |= TEST_ONE_SHIFT(1, 0, u32, 1U << 0, false);
> - err |= TEST_ONE_SHIFT(1, 20, u32, 1U << 20, false);
> - err |= TEST_ONE_SHIFT(1, 31, u32, 1U << 31, false);
> - err |= TEST_ONE_SHIFT(0xFFFFU, 16, u32, 0xFFFFU << 16, false);
> - err |= TEST_ONE_SHIFT(1, 0, u64, 1ULL << 0, false);
> - err |= TEST_ONE_SHIFT(1, 40, u64, 1ULL << 40, false);
> - err |= TEST_ONE_SHIFT(1, 63, u64, 1ULL << 63, false);
> - err |= TEST_ONE_SHIFT(0xFFFFFFFFULL, 32, u64,
> - 0xFFFFFFFFULL << 32, false);
> + TEST_ONE_SHIFT(1, 0, u8, 1 << 0, false);
> + TEST_ONE_SHIFT(1, 4, u8, 1 << 4, false);
> + TEST_ONE_SHIFT(1, 7, u8, 1 << 7, false);
> + TEST_ONE_SHIFT(0xF, 4, u8, 0xF << 4, false);
> + TEST_ONE_SHIFT(1, 0, u16, 1 << 0, false);
> + TEST_ONE_SHIFT(1, 10, u16, 1 << 10, false);
> + TEST_ONE_SHIFT(1, 15, u16, 1 << 15, false);
> + TEST_ONE_SHIFT(0xFF, 8, u16, 0xFF << 8, false);
> + TEST_ONE_SHIFT(1, 0, int, 1 << 0, false);
> + TEST_ONE_SHIFT(1, 16, int, 1 << 16, false);
> + TEST_ONE_SHIFT(1, 30, int, 1 << 30, false);
> + TEST_ONE_SHIFT(1, 0, s32, 1 << 0, false);
> + TEST_ONE_SHIFT(1, 16, s32, 1 << 16, false);
> + TEST_ONE_SHIFT(1, 30, s32, 1 << 30, false);
> + TEST_ONE_SHIFT(1, 0, unsigned int, 1U << 0, false);
> + TEST_ONE_SHIFT(1, 20, unsigned int, 1U << 20, false);
> + TEST_ONE_SHIFT(1, 31, unsigned int, 1U << 31, false);
> + TEST_ONE_SHIFT(0xFFFFU, 16, unsigned int, 0xFFFFU << 16, false);
> + TEST_ONE_SHIFT(1, 0, u32, 1U << 0, false);
> + TEST_ONE_SHIFT(1, 20, u32, 1U << 20, false);
> + TEST_ONE_SHIFT(1, 31, u32, 1U << 31, false);
> + TEST_ONE_SHIFT(0xFFFFU, 16, u32, 0xFFFFU << 16, false);
> + TEST_ONE_SHIFT(1, 0, u64, 1ULL << 0, false);
> + TEST_ONE_SHIFT(1, 40, u64, 1ULL << 40, false);
> + TEST_ONE_SHIFT(1, 63, u64, 1ULL << 63, false);
> + TEST_ONE_SHIFT(0xFFFFFFFFULL, 32, u64, 0xFFFFFFFFULL << 32, false);
>
> /* Sane shift: start and end with 0, without a too-wide shift. */
> - err |= TEST_ONE_SHIFT(0, 7, u8, 0, false);
> - err |= TEST_ONE_SHIFT(0, 15, u16, 0, false);
> - err |= TEST_ONE_SHIFT(0, 31, unsigned int, 0, false);
> - err |= TEST_ONE_SHIFT(0, 31, u32, 0, false);
> - err |= TEST_ONE_SHIFT(0, 63, u64, 0, false);
> + TEST_ONE_SHIFT(0, 7, u8, 0, false);
> + TEST_ONE_SHIFT(0, 15, u16, 0, false);
> + TEST_ONE_SHIFT(0, 31, unsigned int, 0, false);
> + TEST_ONE_SHIFT(0, 31, u32, 0, false);
> + TEST_ONE_SHIFT(0, 63, u64, 0, false);
>
> /* Sane shift: start and end with 0, without reaching signed bit. */
> - err |= TEST_ONE_SHIFT(0, 6, s8, 0, false);
> - err |= TEST_ONE_SHIFT(0, 14, s16, 0, false);
> - err |= TEST_ONE_SHIFT(0, 30, int, 0, false);
> - err |= TEST_ONE_SHIFT(0, 30, s32, 0, false);
> - err |= TEST_ONE_SHIFT(0, 62, s64, 0, false);
> + TEST_ONE_SHIFT(0, 6, s8, 0, false);
> + TEST_ONE_SHIFT(0, 14, s16, 0, false);
> + TEST_ONE_SHIFT(0, 30, int, 0, false);
> + TEST_ONE_SHIFT(0, 30, s32, 0, false);
> + TEST_ONE_SHIFT(0, 62, s64, 0, false);
>
> /* Overflow: shifted the bit off the end. */
> - err |= TEST_ONE_SHIFT(1, 8, u8, 0, true);
> - err |= TEST_ONE_SHIFT(1, 16, u16, 0, true);
> - err |= TEST_ONE_SHIFT(1, 32, unsigned int, 0, true);
> - err |= TEST_ONE_SHIFT(1, 32, u32, 0, true);
> - err |= TEST_ONE_SHIFT(1, 64, u64, 0, true);
> + TEST_ONE_SHIFT(1, 8, u8, 0, true);
> + TEST_ONE_SHIFT(1, 16, u16, 0, true);
> + TEST_ONE_SHIFT(1, 32, unsigned int, 0, true);
> + TEST_ONE_SHIFT(1, 32, u32, 0, true);
> + TEST_ONE_SHIFT(1, 64, u64, 0, true);
>
> /* Overflow: shifted into the signed bit. */
> - err |= TEST_ONE_SHIFT(1, 7, s8, 0, true);
> - err |= TEST_ONE_SHIFT(1, 15, s16, 0, true);
> - err |= TEST_ONE_SHIFT(1, 31, int, 0, true);
> - err |= TEST_ONE_SHIFT(1, 31, s32, 0, true);
> - err |= TEST_ONE_SHIFT(1, 63, s64, 0, true);
> + TEST_ONE_SHIFT(1, 7, s8, 0, true);
> + TEST_ONE_SHIFT(1, 15, s16, 0, true);
> + TEST_ONE_SHIFT(1, 31, int, 0, true);
> + TEST_ONE_SHIFT(1, 31, s32, 0, true);
> + TEST_ONE_SHIFT(1, 63, s64, 0, true);
>
> /* Overflow: high bit falls off unsigned types. */
> /* 10010110 */
> - err |= TEST_ONE_SHIFT(150, 1, u8, 0, true);
> + TEST_ONE_SHIFT(150, 1, u8, 0, true);
> /* 1000100010010110 */
> - err |= TEST_ONE_SHIFT(34966, 1, u16, 0, true);
> + TEST_ONE_SHIFT(34966, 1, u16, 0, true);
> /* 10000100000010001000100010010110 */
> - err |= TEST_ONE_SHIFT(2215151766U, 1, u32, 0, true);
> - err |= TEST_ONE_SHIFT(2215151766U, 1, unsigned int, 0, true);
> + TEST_ONE_SHIFT(2215151766U, 1, u32, 0, true);
> + TEST_ONE_SHIFT(2215151766U, 1, unsigned int, 0, true);
> /* 1000001000010000010000000100000010000100000010001000100010010110 */
> - err |= TEST_ONE_SHIFT(9372061470395238550ULL, 1, u64, 0, true);
> + TEST_ONE_SHIFT(9372061470395238550ULL, 1, u64, 0, true);
>
> /* Overflow: bit shifted into signed bit on signed types. */
> /* 01001011 */
> - err |= TEST_ONE_SHIFT(75, 1, s8, 0, true);
> + TEST_ONE_SHIFT(75, 1, s8, 0, true);
> /* 0100010001001011 */
> - err |= TEST_ONE_SHIFT(17483, 1, s16, 0, true);
> + TEST_ONE_SHIFT(17483, 1, s16, 0, true);
> /* 01000010000001000100010001001011 */
> - err |= TEST_ONE_SHIFT(1107575883, 1, s32, 0, true);
> - err |= TEST_ONE_SHIFT(1107575883, 1, int, 0, true);
> + TEST_ONE_SHIFT(1107575883, 1, s32, 0, true);
> + TEST_ONE_SHIFT(1107575883, 1, int, 0, true);
> /* 0100000100001000001000000010000001000010000001000100010001001011 */
> - err |= TEST_ONE_SHIFT(4686030735197619275LL, 1, s64, 0, true);
> + TEST_ONE_SHIFT(4686030735197619275LL, 1, s64, 0, true);
>
> /* Overflow: bit shifted past signed bit on signed types. */
> /* 01001011 */
> - err |= TEST_ONE_SHIFT(75, 2, s8, 0, true);
> + TEST_ONE_SHIFT(75, 2, s8, 0, true);
> /* 0100010001001011 */
> - err |= TEST_ONE_SHIFT(17483, 2, s16, 0, true);
> + TEST_ONE_SHIFT(17483, 2, s16, 0, true);
> /* 01000010000001000100010001001011 */
> - err |= TEST_ONE_SHIFT(1107575883, 2, s32, 0, true);
> - err |= TEST_ONE_SHIFT(1107575883, 2, int, 0, true);
> + TEST_ONE_SHIFT(1107575883, 2, s32, 0, true);
> + TEST_ONE_SHIFT(1107575883, 2, int, 0, true);
> /* 0100000100001000001000000010000001000010000001000100010001001011 */
> - err |= TEST_ONE_SHIFT(4686030735197619275LL, 2, s64, 0, true);
> + TEST_ONE_SHIFT(4686030735197619275LL, 2, s64, 0, true);
>
> /* Overflow: values larger than destination type. */
> - err |= TEST_ONE_SHIFT(0x100, 0, u8, 0, true);
> - err |= TEST_ONE_SHIFT(0xFF, 0, s8, 0, true);
> - err |= TEST_ONE_SHIFT(0x10000U, 0, u16, 0, true);
> - err |= TEST_ONE_SHIFT(0xFFFFU, 0, s16, 0, true);
> - err |= TEST_ONE_SHIFT(0x100000000ULL, 0, u32, 0, true);
> - err |= TEST_ONE_SHIFT(0x100000000ULL, 0, unsigned int, 0, true);
> - err |= TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, s32, 0, true);
> - err |= TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, int, 0, true);
> - err |= TEST_ONE_SHIFT(0xFFFFFFFFFFFFFFFFULL, 0, s64, 0, true);
> + TEST_ONE_SHIFT(0x100, 0, u8, 0, true);
> + TEST_ONE_SHIFT(0xFF, 0, s8, 0, true);
> + TEST_ONE_SHIFT(0x10000U, 0, u16, 0, true);
> + TEST_ONE_SHIFT(0xFFFFU, 0, s16, 0, true);
> + TEST_ONE_SHIFT(0x100000000ULL, 0, u32, 0, true);
> + TEST_ONE_SHIFT(0x100000000ULL, 0, unsigned int, 0, true);
> + TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, s32, 0, true);
> + TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, int, 0, true);
> + TEST_ONE_SHIFT(0xFFFFFFFFFFFFFFFFULL, 0, s64, 0, true);
>
> /* Nonsense: negative initial value. */
> - err |= TEST_ONE_SHIFT(-1, 0, s8, 0, true);
> - err |= TEST_ONE_SHIFT(-1, 0, u8, 0, true);
> - err |= TEST_ONE_SHIFT(-5, 0, s16, 0, true);
> - err |= TEST_ONE_SHIFT(-5, 0, u16, 0, true);
> - err |= TEST_ONE_SHIFT(-10, 0, int, 0, true);
> - err |= TEST_ONE_SHIFT(-10, 0, unsigned int, 0, true);
> - err |= TEST_ONE_SHIFT(-100, 0, s32, 0, true);
> - err |= TEST_ONE_SHIFT(-100, 0, u32, 0, true);
> - err |= TEST_ONE_SHIFT(-10000, 0, s64, 0, true);
> - err |= TEST_ONE_SHIFT(-10000, 0, u64, 0, true);
> + TEST_ONE_SHIFT(-1, 0, s8, 0, true);
> + TEST_ONE_SHIFT(-1, 0, u8, 0, true);
> + TEST_ONE_SHIFT(-5, 0, s16, 0, true);
> + TEST_ONE_SHIFT(-5, 0, u16, 0, true);
> + TEST_ONE_SHIFT(-10, 0, int, 0, true);
> + TEST_ONE_SHIFT(-10, 0, unsigned int, 0, true);
> + TEST_ONE_SHIFT(-100, 0, s32, 0, true);
> + TEST_ONE_SHIFT(-100, 0, u32, 0, true);
> + TEST_ONE_SHIFT(-10000, 0, s64, 0, true);
> + TEST_ONE_SHIFT(-10000, 0, u64, 0, true);
>
> /* Nonsense: negative shift values. */
> - err |= TEST_ONE_SHIFT(0, -5, s8, 0, true);
> - err |= TEST_ONE_SHIFT(0, -5, u8, 0, true);
> - err |= TEST_ONE_SHIFT(0, -10, s16, 0, true);
> - err |= TEST_ONE_SHIFT(0, -10, u16, 0, true);
> - err |= TEST_ONE_SHIFT(0, -15, int, 0, true);
> - err |= TEST_ONE_SHIFT(0, -15, unsigned int, 0, true);
> - err |= TEST_ONE_SHIFT(0, -20, s32, 0, true);
> - err |= TEST_ONE_SHIFT(0, -20, u32, 0, true);
> - err |= TEST_ONE_SHIFT(0, -30, s64, 0, true);
> - err |= TEST_ONE_SHIFT(0, -30, u64, 0, true);
> + TEST_ONE_SHIFT(0, -5, s8, 0, true);
> + TEST_ONE_SHIFT(0, -5, u8, 0, true);
> + TEST_ONE_SHIFT(0, -10, s16, 0, true);
> + TEST_ONE_SHIFT(0, -10, u16, 0, true);
> + TEST_ONE_SHIFT(0, -15, int, 0, true);
> + TEST_ONE_SHIFT(0, -15, unsigned int, 0, true);
> + TEST_ONE_SHIFT(0, -20, s32, 0, true);
> + TEST_ONE_SHIFT(0, -20, u32, 0, true);
> + TEST_ONE_SHIFT(0, -30, s64, 0, true);
> + TEST_ONE_SHIFT(0, -30, u64, 0, true);
>
> /* Overflow: shifted at or beyond entire type's bit width. */
> - err |= TEST_ONE_SHIFT(0, 8, u8, 0, true);
> - err |= TEST_ONE_SHIFT(0, 9, u8, 0, true);
> - err |= TEST_ONE_SHIFT(0, 8, s8, 0, true);
> - err |= TEST_ONE_SHIFT(0, 9, s8, 0, true);
> - err |= TEST_ONE_SHIFT(0, 16, u16, 0, true);
> - err |= TEST_ONE_SHIFT(0, 17, u16, 0, true);
> - err |= TEST_ONE_SHIFT(0, 16, s16, 0, true);
> - err |= TEST_ONE_SHIFT(0, 17, s16, 0, true);
> - err |= TEST_ONE_SHIFT(0, 32, u32, 0, true);
> - err |= TEST_ONE_SHIFT(0, 33, u32, 0, true);
> - err |= TEST_ONE_SHIFT(0, 32, int, 0, true);
> - err |= TEST_ONE_SHIFT(0, 33, int, 0, true);
> - err |= TEST_ONE_SHIFT(0, 32, s32, 0, true);
> - err |= TEST_ONE_SHIFT(0, 33, s32, 0, true);
> - err |= TEST_ONE_SHIFT(0, 64, u64, 0, true);
> - err |= TEST_ONE_SHIFT(0, 65, u64, 0, true);
> - err |= TEST_ONE_SHIFT(0, 64, s64, 0, true);
> - err |= TEST_ONE_SHIFT(0, 65, s64, 0, true);
> + TEST_ONE_SHIFT(0, 8, u8, 0, true);
> + TEST_ONE_SHIFT(0, 9, u8, 0, true);
> + TEST_ONE_SHIFT(0, 8, s8, 0, true);
> + TEST_ONE_SHIFT(0, 9, s8, 0, true);
> + TEST_ONE_SHIFT(0, 16, u16, 0, true);
> + TEST_ONE_SHIFT(0, 17, u16, 0, true);
> + TEST_ONE_SHIFT(0, 16, s16, 0, true);
> + TEST_ONE_SHIFT(0, 17, s16, 0, true);
> + TEST_ONE_SHIFT(0, 32, u32, 0, true);
> + TEST_ONE_SHIFT(0, 33, u32, 0, true);
> + TEST_ONE_SHIFT(0, 32, int, 0, true);
> + TEST_ONE_SHIFT(0, 33, int, 0, true);
> + TEST_ONE_SHIFT(0, 32, s32, 0, true);
> + TEST_ONE_SHIFT(0, 33, s32, 0, true);
> + TEST_ONE_SHIFT(0, 64, u64, 0, true);
> + TEST_ONE_SHIFT(0, 65, u64, 0, true);
> + TEST_ONE_SHIFT(0, 64, s64, 0, true);
> + TEST_ONE_SHIFT(0, 65, s64, 0, true);
>
> /*
> * Corner case: for unsigned types, we fail when we've shifted
> @@ -472,17 +442,14 @@ static int __init test_overflow_shift(void)
> * signed bit). So, for now, we will test this condition but
> * mark it as not expected to overflow.
> */
> - err |= TEST_ONE_SHIFT(0, 7, s8, 0, false);
> - err |= TEST_ONE_SHIFT(0, 15, s16, 0, false);
> - err |= TEST_ONE_SHIFT(0, 31, int, 0, false);
> - err |= TEST_ONE_SHIFT(0, 31, s32, 0, false);
> - err |= TEST_ONE_SHIFT(0, 63, s64, 0, false);
> -
> - pr_info("%d shift tests finished\n", count);
> + TEST_ONE_SHIFT(0, 7, s8, 0, false);
> + TEST_ONE_SHIFT(0, 15, s16, 0, false);
> + TEST_ONE_SHIFT(0, 31, int, 0, false);
> + TEST_ONE_SHIFT(0, 31, s32, 0, false);
> + TEST_ONE_SHIFT(0, 63, s64, 0, false);
>
> + kunit_info(test, "%d shift tests finished\n", count);
> #undef TEST_ONE_SHIFT
> -
> - return err;
> }
>
> /*
> @@ -502,7 +469,7 @@ static int __init test_overflow_shift(void)
> #define TEST_SIZE (5 * 4096)
>
> #define DEFINE_TEST_ALLOC(func, free_func, want_arg, want_gfp, want_node)\
> -static int __init test_ ## func (void *arg) \
> +static void test_ ## func (struct kunit *test, void *arg) \
> { \
> volatile size_t a = TEST_SIZE; \
> volatile size_t b = (SIZE_MAX / TEST_SIZE) + 1; \
> @@ -510,30 +477,28 @@ static int __init test_ ## func (void *arg) \
> \
> /* Tiny allocation test. */ \
> ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, 1);\
> - if (!ptr) { \
> - pr_warn(#func " failed regular allocation?!\n"); \
> - return 1; \
> - } \
> + KUNIT_EXPECT_FALSE_MSG(test, !ptr, \
> + #func " failed regular allocation?!\n"); \

Optional: we can consider using KUNIT_ASSERT_NOT_ERR_OR_NULL_MSG() here.
It's a more heavy handed than just a `return` on failure, but if the
regular allocation failed, we're probably justified in bailing out on
the whole test case.

> + if (!ptr) \
> + return; \
> free ## want_arg (free_func, arg, ptr); \
> \
> /* Wrapped allocation test. */ \
> ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \
> a * b); \
> - if (!ptr) { \
> - pr_warn(#func " unexpectedly failed bad wrapping?!\n"); \
> - return 1; \
> - } \
> + KUNIT_EXPECT_FALSE_MSG(test, !ptr, \
> + #func " unexpectedly failed bad wrapping?!\n"); \
> + if (!ptr) \
> + return; \
> free ## want_arg (free_func, arg, ptr); \
> \
> /* Saturated allocation test. */ \
> ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \
> array_size(a, b)); \
> - if (ptr) { \
> - pr_warn(#func " missed saturation!\n"); \
> + KUNIT_EXPECT_FALSE_MSG(test, ptr, \
> + #func " missed saturation!\n"); \
> + if (ptr) \

We can instead do

if (ptr) {
KUNIT_FAIL(test, #func "missed saturation!");
free...()
}

IMO, it's a bit easier to read that way, but not that important.

> free ## want_arg (free_func, arg, ptr); \
> - return 1; \
> - } \