Subject: Re: [PATCH 1/3] powerpc: Make NUMA depend on SMP

From: Srikar Dronamraju <[email-masked]>
Date: Wed, 25 Nov 2020 10:00:08 +0530

* Michael Ellerman <[email-masked]> [2020-11-24 23:05:45]:

> Our Kconfig allows NUMA to be enabled without SMP, but none of
> our defconfigs use that combination. This means it can easily be
> broken inadvertently by code changes, which has happened recently.
> 
> Although it's theoretically possible to have a machine with a single
> CPU and multiple memory nodes, I can't think of any real systems where
> that's the case. Even so if such a system exists, it can just run an
> SMP kernel anyway.
> 
> So to avoid the need to add extra #ifdefs and/or build breaks, make
> NUMA depend on SMP.
> 
> Reported-by: kernel test robot <[email-masked]>
> Reported-by: Randy Dunlap <[email-masked]>
> Signed-off-by: Michael Ellerman <[email-masked]>

Looks good to me.

Reviewed-by: Srikar Dronamraju <[email-masked]>
> ---
>  arch/powerpc/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index e9f13fe08492..a22db3db6b96 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -660,7 +660,7 @@ config IRQ_ALL_CPUS
> 
>  config NUMA
>  	bool "NUMA support"
> -	depends on PPC64
> +	depends on PPC64 && SMP
>  	default y if SMP && PPC_PSERIES
> 
>  config NODES_SHIFT
> -- 
> 2.25.1
> 

-- 
Thanks and Regards
Srikar Dronamraju