The compiler is smart enough to insert a call to memset() in
riscv_vdso_get_cpus(), which generates a dynamic relocation.

So prevent this by using -fno-builtin option.

Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
---
 arch/riscv/kernel/vdso/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index 960feb1526ca..3f1c4b2d0b06 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -18,6 +18,7 @@ obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
 
 ccflags-y := -fno-stack-protector
 ccflags-y += -DDISABLE_BRANCH_PROFILING
+ccflags-y += -fno-builtin
 
 ifneq ($(c-gettimeofday-y),)
   CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
-- 
2.39.2

On Wed, Oct 16, 2024 at 4:37 PM Alexandre Ghiti <alexghiti@rivosinc.com> wrote:
>
> The compiler is smart enough to insert a call to memset() in
> riscv_vdso_get_cpus(), which generates a dynamic relocation.
>
> So prevent this by using -fno-builtin option.
>
> Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API")
> Cc: stable@vger.kernel.org
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
> ---
>  arch/riscv/kernel/vdso/Makefile | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
> index 960feb1526ca..3f1c4b2d0b06 100644
> --- a/arch/riscv/kernel/vdso/Makefile
> +++ b/arch/riscv/kernel/vdso/Makefile
> @@ -18,6 +18,7 @@ obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
>
>  ccflags-y := -fno-stack-protector
>  ccflags-y += -DDISABLE_BRANCH_PROFILING
> +ccflags-y += -fno-builtin
LGTM!
Reviewed-by: Guo Ren <guoren@kernel.org>

>
>  ifneq ($(c-gettimeofday-y),)
>    CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
> --
> 2.39.2
>


-- 
Best Regards
 Guo Ren