Re: [PATCH v3 1/4] x86/spec: print the built-in SPECULATIVE_HARDEN_* options

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.02.2024 12:07, Roger Pau Monne wrote:
> Just like it's done for INDIRECT_THUNK and SHADOW_PAGING.
> 
> Reported-by: Jan Beulich <jbeulich@xxxxxxxx>
> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

In principle
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
but ...

> --- a/xen/arch/x86/spec_ctrl.c
> +++ b/xen/arch/x86/spec_ctrl.c
> @@ -466,13 +466,25 @@ static void __init print_details(enum ind_thunk thunk)
>             (e21a & cpufeat_mask(X86_FEATURE_SBPB))           ? " SBPB"       
>     : "");
>  
>      /* Compiled-in support which pertains to mitigations. */
> -    if ( IS_ENABLED(CONFIG_INDIRECT_THUNK) || 
> IS_ENABLED(CONFIG_SHADOW_PAGING) )
> +    if ( IS_ENABLED(CONFIG_INDIRECT_THUNK) || 
> IS_ENABLED(CONFIG_SHADOW_PAGING) ||
> +         IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_ARRAY) ||
> +         IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_BRANCH) ||
> +         IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_GUEST_ACCESS) )
>          printk("  Compiled-in support:"
>  #ifdef CONFIG_INDIRECT_THUNK
>                 " INDIRECT_THUNK"
>  #endif
>  #ifdef CONFIG_SHADOW_PAGING
>                 " SHADOW_PAGING"
> +#endif
> +#ifdef CONFIG_SPECULATIVE_HARDEN_ARRAY
> +               " SPECULATIVE_HARDEN_ARRAY"
> +#endif
> +#ifdef CONFIG_SPECULATIVE_HARDEN_BRANCH
> +               " SPECULATIVE_HARDEN_BRANCH"
> +#endif
> +#ifdef CONFIG_SPECULATIVE_HARDEN_GUEST_ACCESS
> +               " SPECULATIVE_HARDEN_GUEST_ACCESS"
>  #endif

... I'd like to suggest to drop the SPECULATIVE_ from the string literals.
They're relevant in the Kconfig identifiers, but they're imo redundant in
the context of these log messages. (Happy to adjust while committing, if
need be.)

Jan