After an innocuous optimization change in clang-22, allmodconfig (which
enables CONFIG_KASAN and CONFIG_WERROR) breaks with:
drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c:1724:6:
error: stack frame size (3144) exceeds limit (3072) in
'dml32_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than]
1724 | void dml32_ModeSupportAndSystemConfigurationFull(struct
display_mode_lib *mode_lib)
| ^
With clang-21, this function was already pretty close to the existing
limit of 3072 bytes.
drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c:1724:6:
error: stack frame size (2904) exceeds limit (2048) in
'dml32_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than]
1724 | void dml32_ModeSupportAndSystemConfigurationFull(struct
display_mode_lib *mode_lib)
| ^
A similar situation occurred in dml2, which was resolved by
commit e4479aecf658 ("drm/amd/display: Increase sanitizer frame larger
than limit when compile testing with clang") by increasing the limit for
clang when compile testing with certain sanitizer enabled, so that
allmodconfig (an easy testing target) continues to work.
Apply that same change to the dml folder to clear up the warning for
allmodconfig, unbreaking the build.
Cc: [email protected]
Closes: https://github.com/ClangBuiltLinux/linux/issues/2135
Signed-off-by: Nathan Chancellor <[email protected]>
---
drivers/gpu/drm/amd/display/dc/dml/Makefile | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile
b/drivers/gpu/drm/amd/display/dc/dml/Makefile
index b357683b4255..268b5fbdb48b 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/Makefile
+++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile
@@ -30,7 +30,11 @@ dml_rcflags := $(CC_FLAGS_NO_FPU)
ifneq ($(CONFIG_FRAME_WARN),0)
ifeq ($(filter y,$(CONFIG_KASAN)$(CONFIG_KCSAN)),y)
- frame_warn_limit := 3072
+ ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_COMPILE_TEST),yy)
+ frame_warn_limit := 4096
+ else
+ frame_warn_limit := 3072
+ endif
else
frame_warn_limit := 2048
endif
---
base-commit: f24e96d69f5b9eb0f3b9c49e53c385c50729edfd
change-id: 20251213-dml-bump-frame-warn-clang-sanitizers-0a34fc916aec
Best regards,
--
Nathan Chancellor <[email protected]>
