Re: [PATCH v5 25/29] arm64: allow LTO_CLANG and THINLTO to be selected

From: Will Deacon
Date: Mon Oct 12 2020 - 04:31:32 EST


On Fri, Oct 09, 2020 at 09:13:34AM -0700, Sami Tolvanen wrote:
> Allow CONFIG_LTO_CLANG and CONFIG_THINLTO to be enabled.
>
> Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
> arch/arm64/Kconfig | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index ad522b021f35..7016d193864f 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -72,6 +72,8 @@ config ARM64
> select ARCH_USE_SYM_ANNOTATIONS
> select ARCH_SUPPORTS_MEMORY_FAILURE
> select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
> + select ARCH_SUPPORTS_LTO_CLANG
> + select ARCH_SUPPORTS_THINLTO

Please don't enable this for arm64 until we have the dependency stuff sorted
out. I posted patches [1] for this before, but I think they should be part
of this series as they don't make sense on their own.

Will

[1] https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/log/?h=rwonce/read-barrier-depends