The patch titled
Subject: drm: suppress intentional warning backtraces in scaling unit tests
has been added to the -mm mm-nonmm-unstable branch. Its filename is
drm-suppress-intentional-warning-backtraces-in-scaling-unit-tests.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/drm-suppress-intentional-warning-backtraces-in-scaling-unit-tests.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Guenter Roeck <linux@xxxxxxxxxxxx>
Subject: drm: suppress intentional warning backtraces in scaling unit tests
Date: Thu, 13 Mar 2025 11:43:20 +0000
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 and distraction from real problems.
Link: https://lkml.kernel.org/r/20250313114329.284104-6-acarmina@xxxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Alessandro Carminati <acarmina@xxxxxxxxxx>
Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Acked-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: MaÃra Canal <mcanal@xxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Arthur Grillo <arthurgrillo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brendan Higgins <brendan.higgins@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Charlie Jenkins <charlie@xxxxxxxxxxxx>
Cc: Daniel Diaz <daniel.diaz@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David Gow <davidgow@xxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Rae Moar <rmoar@xxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Simon Horman <horms@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Thomas Zimemrmann <tzimmermann@xxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/tests/drm_rect_test.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
--- a/drivers/gpu/drm/tests/drm_rect_test.c~drm-suppress-intentional-warning-backtraces-in-scaling-unit-tests
+++ a/drivers/gpu/drm/tests/drm_rect_test.c
@@ -406,22 +406,38 @@ KUNIT_ARRAY_PARAM(drm_rect_scale, drm_re
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;
+ /*
+ * 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.
+ */
+ KUNIT_START_SUPPRESSED_WARNING(drm_calc_scale);
scaling_factor = drm_rect_calc_hscale(¶ms->src, ¶ms->dst,
params->min_range, params->max_range);
+ KUNIT_END_SUPPRESSED_WARNING(drm_calc_scale);
KUNIT_EXPECT_EQ(test, scaling_factor, params->expected_scaling_factor);
}
static void drm_test_rect_calc_vscale(struct kunit *test)
{
+ DEFINE_SUPPRESSED_WARNING(drm_calc_scale);
const struct drm_rect_scale_case *params = test->param_value;
int scaling_factor;
+ /*
+ * drm_rect_calc_vscale() generates a warning backtrace whenever bad
+ * parameters are passed to it. This affects all unit tests with an
+ * error code in expected_scaling_factor.
+ */
+ KUNIT_START_SUPPRESSED_WARNING(drm_calc_scale);
scaling_factor = drm_rect_calc_vscale(¶ms->src, ¶ms->dst,
params->min_range, params->max_range);
+ KUNIT_END_SUPPRESSED_WARNING(drm_calc_scale);
KUNIT_EXPECT_EQ(test, scaling_factor, params->expected_scaling_factor);
}
_
Patches currently in -mm which might be from linux@xxxxxxxxxxxx are
bug-kunit-core-support-for-suppressing-warning-backtraces.patch
kunit-bug-count-suppressed-warning-backtraces.patch
kunit-add-test-cases-for-backtrace-warning-suppression.patch
kunit-add-documentation-for-warning-backtrace-suppression-api.patch
drm-suppress-intentional-warning-backtraces-in-scaling-unit-tests.patch
x86-add-support-for-suppressing-warning-backtraces.patch
arm64-add-support-for-suppressing-warning-backtraces.patch
loongarch-add-support-for-suppressing-warning-backtraces.patch
parisc-add-support-for-suppressing-warning-backtraces.patch
s390-add-support-for-suppressing-warning-backtraces.patch
sh-add-support-for-suppressing-warning-backtraces.patch
sh-move-defines-needed-for-suppressing-warning-backtraces.patch
riscv-add-support-for-suppressing-warning-backtraces.patch
powerpc-add-support-for-suppressing-warning-backtraces.patch
