Re: [PATCH] MIPS: select ARCH_KEEP_MEMBLOCK unconditionally

[Guenter Roeck <linux@roeck-us.net>]

On Wed, Apr 07, 2021 at 10:35:43AM -0700, Nick Desaulniers wrote:
> While removing allnoconfig_y from Kconfig, ARCH=mips allnoconfig builds
> started failing with the error:
> 
> WARNING: modpost: vmlinux.o(.text+0x9c70): Section mismatch in reference
> from the function reserve_exception_space() to the function
> .meminit.text:memblock_reserve()
> The function reserve_exception_space() references the function __meminit
> memblock_reserve().
> This is often because reserve_exception_space lacks a __meminit
> annotation or the annotation of memblock_reserve is wrong.
> ERROR: modpost: Section mismatches detected.
> Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.
> 
> allnoconfig disables DEBUG_KERNEL and thus ARCH_KEEP_MEMBLOCK, which
> changes __init_memblock to be equivalent to __meminit triggering the
> above error.
> 
> Link: https://lore.kernel.org/linux-kbuild/20210313194836.372585-11-masahiroy@kernel.org/
> Fixes: commit a8c0f1c634507 ("MIPS: Select ARCH_KEEP_MEMBLOCK if

s/commit //

> DEBUG_KERNEL to enable sysfs memblock debug")
> Cc: Masahiro Yamada <masahiroy@kernel.org>
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Tested-by: Guenter Roeck <linux@roeck-us.net>

Guenter

> ---
>  arch/mips/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index e9893cd34992..702648f60e41 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -12,7 +12,7 @@ config MIPS
>  	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>  	select ARCH_HAS_UBSAN_SANITIZE_ALL
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_KEEP_MEMBLOCK if DEBUG_KERNEL
> +	select ARCH_KEEP_MEMBLOCK
>  	select ARCH_SUPPORTS_UPROBES
>  	select ARCH_USE_BUILTIN_BSWAP
>  	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
> -- 
> 2.31.1.295.g9ea45b61b8-goog
>