When CONFIG_PPC64 is set and CONFIG_ALTIVEC is not the following build failures occur: drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c: In function 'dc_fpu_begin': >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c:61:17: error: implicit declaration of function 'enable_kernel_altivec'; did you mean 'enable_kernel_vsx'? [-Werror=implicit-function-declaration] 61 | enable_kernel_altivec(); | ^~~~~~~~~~~~~~~~~~~~~ | enable_kernel_vsx drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c: In function 'dc_fpu_end': >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c:89:17: error: implicit declaration of function 'disable_kernel_altivec'; did you mean 'disable_kernel_vsx'? [-Werror=implicit-function-declaration] 89 | disable_kernel_altivec(); | ^~~~~~~~~~~~~~~~~~~~~~ | disable_kernel_vsx cc1: some warnings being treated as errors This commit adds stub instances of both enable_kernel_altivec() and disable_kernel_altivec() the same way as done in commit bd73758803c2 regarding enable_kernel_vsx() and disable_kernel_vsx(). Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Magali Lemes <magalilemes00@xxxxxxxxx> --- arch/powerpc/include/asm/switch_to.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 1f43ef696033..aee25e3ebf96 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -62,6 +62,15 @@ static inline void disable_kernel_altivec(void) #else static inline void save_altivec(struct task_struct *t) { } static inline void __giveup_altivec(struct task_struct *t) { } +static inline void enable_kernel_altivec(void) +{ + BUILD_BUG(); +} + +static inline void disable_kernel_altivec(void) +{ + BUILD_BUG(); +} #endif #ifdef CONFIG_VSX -- 2.25.1