Re: [PATCH v2] powerpc/64s: support nospectre_v2 cmdline option

[Michael Ellerman]

"Christopher M. Riedl" <c...@informatik.wtf> writes:
> diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
> index b33bafb8fcea..d775da9b9227 100644
> --- a/arch/powerpc/kernel/security.c
> +++ b/arch/powerpc/kernel/security.c
> @@ -391,6 +394,15 @@ static void toggle_count_cache_flush(bool enable)
>  
>  void setup_count_cache_flush(void)
>  {
> +     if (no_spectrev2) {
> +             if (security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED)
> +                 || security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED))
> +                     pr_warn("Spectre v2 mitigations not under software 
> control, can't disable\n");
> +
> +             toggle_count_cache_flush(false);
> +             return;
> +     }
> +
>       toggle_count_cache_flush(true);
>  }

I'm nit-picking, but would it be better as:

void setup_count_cache_flush(void)
{
        bool enable = true;

        if (no_spectrev2) {
                if (security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED)
                    || security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED))
                        pr_warn("Spectre v2 mitigations not under software 
control, can't disable\n");

                enable = false;
        }

        toggle_count_cache_flush(enable);
}

???

cheers