Re: [PATCH 09/12] riscv: add RISC-V Svpbmt extension support

[Christoph Hellwig]

> +config RISCV_ISA_SVPBMT
> +	bool "SVPBMT extension support"

I don't think this prompt is very useful as it doesn't describe
what it does.  But do we even want people to disable it as it is
really essentially for a fully functioning kernel and a pity that
it took RISC-V so long to get there?

> +	depends on 64BIT && MMU
> +	select RISCV_ALTERNATIVE
> +	default y
> +	help
> +	   Adds support to dynamically detect the presence of the SVPBMT extension

overly long line here.

> index 5f1046e82d9f..dbfcd9b72bd8 100644
> --- a/arch/riscv/include/asm/errata_list.h
> +++ b/arch/riscv/include/asm/errata_list.h
> @@ -14,6 +14,9 @@
>  #define	ERRATA_SIFIVE_NUMBER 2
>  #endif
>  
> +#define	CPUFEATURE_SVPBMT 0
> +#define	CPUFEATURE_NUMBER 1

is errata_list.h really the right place for architectural features?

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>