[PATCH 1/2] riscv: Hoist linker relaxation disabling logic into Kconfig

[Fangrui Song]

On Wed, Nov 29, 2023 at 3:30 PM Nathan Chancellor <nathan at kernel.org> wrote:
>
> Certain configurations may need to be disabled if linker relaxation is
> in use, such as DWARF5 with ld.lld < 18. Hoist the logic of whether or
> not linker relaxation is in use into Kconfig so decisions can be made at
> configuration time.
>
> Signed-off-by: Nathan Chancellor <nathan at kernel.org>
> ---
>  arch/riscv/Kconfig  | 5 +++++
>  arch/riscv/Makefile | 4 +---
>  2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 95a2a06acc6a..72be1d8122a3 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -181,6 +181,11 @@ config HAVE_SHADOW_CALL_STACK
>         # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
>         depends on $(ld-option,--no-relax-gp)
>
> +config RISCV_USE_LINKER_RELAXATION
> +       def_bool y
> +       # https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
> +       depends on !LD_IS_LLD || LLD_VERSION >= 150000
> +
>  config ARCH_MMAP_RND_BITS_MIN
>         default 18 if 64BIT
>         default 8
> diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
> index a74be78678eb..e383aa9e2757 100644
> --- a/arch/riscv/Makefile
> +++ b/arch/riscv/Makefile
> @@ -43,8 +43,7 @@ else
>         KBUILD_LDFLAGS += -melf32lriscv
>  endif
>
> -ifeq ($(CONFIG_LD_IS_LLD),y)
> -ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 150000),y)
> +ifndef CONFIG_RISCV_USE_LINKER_RELAXATION
>         KBUILD_CFLAGS += -mno-relax
>         KBUILD_AFLAGS += -mno-relax
>  ifndef CONFIG_AS_IS_LLVM
> @@ -52,7 +51,6 @@ ifndef CONFIG_AS_IS_LLVM
>         KBUILD_AFLAGS += -Wa,-mno-relax
>  endif
>  endif
> -endif
>
>  ifeq ($(CONFIG_SHADOW_CALL_STACK),y)
>         KBUILD_LDFLAGS += --no-relax-gp
>
> --
> 2.43.0


Reviewed-by: Fangrui Song <maskray at google.com>


-- 
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