On Wed, Mar 02, 2022 at 04:59:09PM -0700, Nathan Chancellor wrote:
> Clang warns on certain 32-bit architectures:
>
> drivers/gpu/drm/selftests/test-drm_plane_helper.c:76:5: warning: stack frame size (1064) exceeds limit (1024) in 'igt_check_plane_state' [-Wframe-larger-than]
> int igt_check_plane_state(void *ignored)
> ^
> 1 warning generated.
>
> The structures in igt_check_plane_state() total 1008 bytes, so any small
> amount of inlining will cause the stack frame to exceed the 32-bit limit
> of 1024, triggering the warning.
>
> Move these structures to static storage, which dramatically reduces the
> amount of stack space in igt_check_plane_state(). There is no testing
> impact, as igt_check_plane_state() is only called once in the driver.
>
> Fixes: 943e6a8beeac ("mock a drm_plane in igt_check_plane_state to make the test more robust")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1600
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Note that the offending patch is now in mainline and results in test build
failures there.
Building csky:allmodconfig ... failed
--------------
Error log:
drivers/gpu/drm/selftests/test-drm_plane_helper.c: In function 'igt_check_plane_state':
drivers/gpu/drm/selftests/test-drm_plane_helper.c:223:1: error: the frame size of 1072 bytes is larger than 1024 bytes
This is with gcc 11.2.
Guenter
