Re: [RFC PATCH 15/34] x86/bugs: Restructure ssb mitigation

[Nikolay Borisov]

On 12.09.24 г. 22:08 ч., David Kaplan wrote:
> Restructure ssb to use select/apply functions to create consistent
> vulnerability handling.
>
> Signed-off-by: David Kaplan <david.kaplan@xxxxxxx>
> ---
>   arch/x86/kernel/cpu/bugs.c | 26 ++++++++++++++++----------
>   1 file changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
> index 32ebe9e934fe..c996c1521851 100644
> --- a/arch/x86/kernel/cpu/bugs.c
> +++ b/arch/x86/kernel/cpu/bugs.c
> @@ -65,6 +65,7 @@ static void __init spectre_v2_user_select_mitigation(void);
>   static void __init spectre_v2_user_update_mitigation(void);
>   static void __init spectre_v2_user_apply_mitigation(void);
>   static void __init ssb_select_mitigation(void);
> +static void __init ssb_apply_mitigation(void);
>   static void __init l1tf_select_mitigation(void);
>   static void __init mds_select_mitigation(void);
>   static void __init mds_update_mitigation(void);
> @@ -223,6 +224,7 @@ void __init cpu_select_mitigations(void)
>   	spectre_v2_apply_mitigation();
>   	retbleed_apply_mitigation();
>   	spectre_v2_user_apply_mitigation();
> +	ssb_apply_mitigation();
>   	mds_apply_mitigation();
>   	taa_apply_mitigation();
>   	mmio_apply_mitigation();
> @@ -2211,13 +2213,26 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
>   		break;
>   	}
>   
> +	return mode;
> +}
> +
> +static void ssb_select_mitigation(void)
> +{
> +	ssb_mode = __ssb_select_mitigation();
> +
> +	if (boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
> +		pr_info("%s\n", ssb_strings[ssb_mode]);
> +}

nit: While at it simply open code __ssb_select_mitigation() here.

<snip>