Re: [PATCH v2 24/28] arm: Add support for generic vDSO

Vincenzo Frascino
2018-12-11T14:16:00Z

Hi Marc,

thank you very much for testing this set. I really appreciate it.

On 10/12/2018 22:13, Mark Salyzyn wrote:
> On 11/29/2018 09:05 AM, Vincenzo Frascino wrote:
>> The arm vDSO library requires some adaptations to use to take advantage
>> of the newly introduced generic vDSO library.
> Tested-by? Would like to note that this patch series up to 24/28 was
> back-ported to android-4.9 and worked successfully on a Hikey arm64 device.
>

I will add you as Tested-by in the next version of the patches. I am going to
re-issue a v3 based on the comments that Arnd and Thomas provided. Would you be
interested in testing it as well? If so I can integrate the support for clang
based on what your are suggesting below to make it more straight forward for
you. Let me know.

> Only significant change was to add back support for clang in
> arch/arm64/Makefile (pseudo patch):
>
>  ifeq ($(CONFIG_GENERIC_COMPAT_VDSO), y)
>    CROSS_COMPILE_ARM32 ?= $(CONFIG_CROSS_COMPILE_COMPAT_VDSO:"%"=%)
>
>    ifeq ($(CROSS_COMPILE_ARM32),)
>      $(error CROSS_COMPILE_ARM32 not defined or empty, the compat vDSO
> will not be built)
> +   else ifeq ($(cc-name),clang)
> +     export CLANG_TRIPLE_ARM32 ?= $(CROSS_COMPILE_ARM32)
> +     export CLANG_TARGET_ARM32 := --target=$(notdir
> $(CLANG_TRIPLE_ARM32:%-=%))
> +     export CONFIG_COMPAT_VDSO := y
> +     compat_vdso := -DCONFIG_COMPAT_VDSO=1
> -+   else ifeq ($(shell which $(CROSS_COMPILE_ARM32)$(cc-name) 2>
> /dev/null),)
> -+     $(error $(CROSS_COMPILE_ARM32)$(cc-name) not found, check
> CROSS_COMPILE_ARM32)
>    else
>      export CROSS_COMPILE_ARM32
>      export CONFIG_COMPAT_VDSO := y
>      compat_vdso := -DCONFIG_COMPAT_VDSO=1
>    endif
>  endif
>
> -- Mark
>

--
Regards,
Vincenzo