Re: [PATCH] kernel/cpu/bugs: log ltf1 mitigation status

From: Borislav Petkov
Date: Mon Jun 02 2025 - 05:10:16 EST


On Mon, Jun 02, 2025 at 07:37:06AM +0000, Khalid Ali wrote:
> Log the L1TF mitigation like other mitigatioons. This one is is the
> only one that doesn't get logged.
>
> Signed-off-by: Khalid Ali <khaliidcaliy@xxxxxxxxx>
> ---
> arch/x86/kernel/cpu/bugs.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
> index 7f94e6a5497d..38cb2a1b2849 100644
> --- a/arch/x86/kernel/cpu/bugs.c
> +++ b/arch/x86/kernel/cpu/bugs.c
> @@ -2803,6 +2803,7 @@ static void __init l1tf_apply_mitigation(void)
> return;
> }
>
> + pr_info("Mitigation: PTE inversion\n");
> setup_force_cpu_cap(X86_FEATURE_L1TF_PTEINV);
> }

Pawan, what's the story here?

There's this stuff further down in that file:

| #define L1TF_DEFAULT_MSG "Mitigation: PTE Inversion"
|
| #if IS_ENABLED(CONFIG_KVM_INTEL)
| static const char * const l1tf_vmx_states[] = {

which comes from 2018:

72c6d2db64fa ("x86/litf: Introduce vmx status variable")

I guess it is about time we made this mitigation also follow the common
pattern with the mitigation strings and issuing them at the right time?

:-)

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette