Re: [tip: x86/pti] x86/speculation: Fix redundant MDS mitigation message

From: Waiman Long
Date: Sun Nov 17 2019 - 20:23:01 EST


On 11/16/19 9:24 AM, Borislav Petkov wrote:
> On Sat, Nov 16, 2019 at 12:25:19PM -0000, tip-bot2 for Waiman Long wrote:
>> +static void __init mds_print_mitigation(void)
>> +{
>> pr_info("%s\n", mds_strings[mds_mitigation]);
>> }
> Almost. This causes
>
> MDS: Vulnerable
>
> to be printed on an in-order 32-bit Atom here, which is wrong. I've
> fixed it up to:
>
> ---
> diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
> index cb2fbd93ef4d..8bf64899f56a 100644
> --- a/arch/x86/kernel/cpu/bugs.c
> +++ b/arch/x86/kernel/cpu/bugs.c
> @@ -256,6 +256,9 @@ static void __init mds_select_mitigation(void)
>
> static void __init mds_print_mitigation(void)
> {
> + if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off())
> + return;
> +
> pr_info("%s\n", mds_strings[mds_mitigation]);
> }
>
>
You are right. I missed that.

Thanks for fixing it.

Cheers,
Longman