-Wframe-larger-than in drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c

[nathanchance]

$ cat allno.config
CONFIG_DRM=y
CONFIG_DRM_AMDGPU=y
CONFIG_DRM_AMD_DC=y
CONFIG_KASAN=y
CONFIG_PCI=y

$ make -skj"$(nproc)" ARCH=x86_64 KCONFIG_ALLCONFIG=1 LLVM=1 clean allnoconfig drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.o
drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c:1724:6: warning: stack frame size (3256) exceeds limit (3072) in 'dml32_ModeSupportAndSystemConfigurationFull' [-Wframe-larger-than]
 1724 | void dml32_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib)
      |      ^
1 warning generated.

With LLVM 21.1.3 or CONFIG_KASAN=y omitted from allno.config, there is no warning. I am pretty sure I did a bisect on this and the commit it landed on seemed innocuous but I will redo it later to get a better understanding of what happens here.

[nathanchance]

https://lore.kernel.org/20251213-dml-bump-frame-warn-clang-sanitizers-v1-1-0e91608db9eb@kernel.org/

While this does not actually resolve the warning in the configuration listed above, it avoids the warning for allmodconfig, where it breaks the build due to CONFIG_WERROR.