Re: [PATCH 08/11] lib: consolidate the GENERIC_BUG symbol

From: Masahiro Yamada
Date: Fri Feb 15 2019 - 03:43:15 EST


On Thu, Feb 14, 2019 at 2:40 AM Christoph Hellwig <hch@xxxxxx> wrote:
>
> And just let the architectures that want it select the symbol.
> Same for GENERIC_BUG_RELATIVE_POINTERS.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>


This slightly changes the behavior of GENERIC_BUG_RELATIVE_POINTERS
for arm64, riscv, x86.
Previously, GENERIC_BUG_RELATIVE_POINTERS was enabled only when BUG=y.


Having said that, this is not a big deal.
When CONFIG_GENERIC_BUG=n, CONFIG_GENERIC_BUG_RELATIVE_POINTERS
is actually don't care.



If you change this,
could you add some comments in commit description?


> ---

> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index c39dac831f08..913b2ca7ec22 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -85,6 +85,8 @@ config ARM64
> select FRAME_POINTER
> select GENERIC_ALLOCATOR
> select GENERIC_ARCH_TOPOLOGY
> + select GENERIC_BUG if BUG
> + select GENERIC_BUG_RELATIVE_POINTERS

Precisely,

select GENERIC_BUG_RELATIVE_POINTERS if BUG




> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 732614eb3683..c410ed896567 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -19,6 +19,8 @@ config RISCV
> select ARCH_WANT_FRAME_POINTERS
> select CLONE_BACKWARDS
> select COMMON_CLK
> + select GENERIC_BUG if BUG
> + select GENERIC_BUG_RELATIVE_POINTERS if 64BIT

Precisely,

select GENERIC_BUG_RELATIVE_POINTERS if 64BIT && BUG


> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index 15ccdd04814e..2a5c12be633e 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -17,12 +17,6 @@ config ARCH_HAS_ILOG2_U64
> config GENERIC_HWEIGHT
> def_bool y
>
> -config GENERIC_BUG
> - def_bool y if BUG
> -
> -config GENERIC_BUG_RELATIVE_POINTERS
> - def_bool y
> -


Hmm, s390 enables GENERIC_BUG_RELATIVE_POINTERS
irrespective of BUG...





> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 1bd4f19b6b28..f4cb31174e1b 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -91,6 +91,8 @@ config X86
> select DCACHE_WORD_ACCESS
> select EDAC_ATOMIC_SCRUB
> select EDAC_SUPPORT
> + select GENERIC_BUG if BUG
> + select GENERIC_BUG_RELATIVE_POINTERS if X86_64

Precisely,

select GENERIC_BUG_RELATIVE_POINTERS if X86_64 && BUG






--
Best Regards
Masahiro Yamada