Re: [PATCH v2 05/14] drm: Suppress intentional warning backtraces in scaling unit tests

From: Guenter Roeck <linux@roeck-us.net>
To: "Maíra Canal" <mcanal@igalia.com>
Cc: loongarch@lists.linux.dev, linux-doc@vger.kernel.org,
	dri-devel@lists.freedesktop.org,
	"Brendan Higgins" <brendan.higgins@linux.dev>,
	linux-kselftest@vger.kernel.org, linux-riscv@lists.infradead.org,
	"David Airlie" <airlied@gmail.com>,
	"Arthur Grillo" <arthurgrillo@riseup.net>,
	"Ville Syrjälä" <ville.syrjala@linux.intel.com>,
	linux-arch@vger.kernel.org, linux-s390@vger.kernel.org,
	"Daniel Diaz" <daniel.diaz@linaro.org>,
	"Naresh Kamboju" <naresh.kamboju@linaro.org>,
	linux-sh@vger.kernel.org,
	"Dan Carpenter" <dan.carpenter@linaro.org>,
	"Linux Kernel Functional Testing" <lkft@linaro.org>,
	"Kees Cook" <keescook@chromium.org>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Maarten Lankhorst" <maarten.lankhorst@linux.intel.com>,
	"Maxime Ripard" <mripard@kernel.org>,
	"David Gow" <davidgow@google.com>,
	"Daniel Vetter" <daniel@ffwll.ch>,
	linux-arm-kernel@lists.infradead.org, kunit-dev@googlegroups.com,
	linux-parisc@vger.kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 05/14] drm: Suppress intentional warning backtraces in scaling unit tests
Date: Mon, 25 Mar 2024 22:02:33 -0700	[thread overview]
Message-ID: <4799424e-8dfc-4848-8c4f-affedaec9dfe@roeck-us.net> (raw)
In-Reply-To: <7f6a223f-f432-4e1b-a67e-3816448224a1@igalia.com>

On 3/25/24 18:09, Maíra Canal wrote:
> On 3/25/24 16:24, Guenter Roeck wrote:
>> Hi,
>>
>> On Mon, Mar 25, 2024 at 04:05:06PM -0300, Maíra Canal wrote:
>>> Hi Guenter,
>>>
>>> On 3/25/24 14:52, Guenter Roeck wrote:
>>>> The drm_test_rect_calc_hscale and drm_test_rect_calc_vscale unit tests
>>>> intentionally trigger warning backtraces by providing bad parameters to
>>>> the tested functions. What is tested is the return value, not the existence
>>>> of a warning backtrace. Suppress the backtraces to avoid clogging the
>>>> kernel log.
>>>>
>>>> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
>>>> Acked-by: Dan Carpenter <dan.carpenter@linaro.org>
>>>> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
>>>> ---
>>>> - Rebased to v6.9-rc1
>>>> - Added Tested-by:, Acked-by:, and Reviewed-by: tags
>>>>
>>>>    drivers/gpu/drm/tests/drm_rect_test.c | 6 ++++++
>>>>    1 file changed, 6 insertions(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/tests/drm_rect_test.c b/drivers/gpu/drm/tests/drm_rect_test.c
>>>> index 76332cd2ead8..75614cb4deb5 100644
>>>> --- a/drivers/gpu/drm/tests/drm_rect_test.c
>>>> +++ b/drivers/gpu/drm/tests/drm_rect_test.c
>>>> @@ -406,22 +406,28 @@ KUNIT_ARRAY_PARAM(drm_rect_scale, drm_rect_scale_cases, drm_rect_scale_case_desc
>>>>    static void drm_test_rect_calc_hscale(struct kunit *test)
>>>>    {
>>>> +    DEFINE_SUPPRESSED_WARNING(drm_calc_scale);
>>>>        const struct drm_rect_scale_case *params = test->param_value;
>>>>        int scaling_factor;
>>>> +    START_SUPPRESSED_WARNING(drm_calc_scale);
>>>
>>> I'm not sure if it is not that obvious only to me, but it would be nice
>>> to have a comment here, remembering that we provide bad parameters in
>>> some test cases.
>>
>> Sure. Something like this ?
>>
>>          /*
>>           * drm_rect_calc_hscale() generates a warning backtrace whenever bad
>>           * parameters are passed to it. This affects all unit tests with an
>>           * error code in expected_scaling_factor.
>>           */
>>
> 
> Yeah, perfect. With that, feel free to add my
> 
> Acked-by: Maíra Canal <mcanal@igalia.com>
> 

Thanks!
Guenter