RE: [PATCH v3 05/35] x86/bugs: Restructure taa mitigation

[Kaplan, David]

[AMD Official Use Only - AMD Internal Distribution Only]

> -----Original Message-----
> From: Brendan Jackman <jackmanb@xxxxxxxxxx>
> Sent: Monday, February 10, 2025 10:25 AM
> To: Kaplan, David <David.Kaplan@xxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>; Peter
> Zijlstra <peterz@xxxxxxxxxxxxx>; Josh Poimboeuf <jpoimboe@xxxxxxxxxx>; Pawan
> Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx>; Ingo Molnar <mingo@xxxxxxxxxx>;
> Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>; x86@xxxxxxxxxx; H . Peter Anvin
> <hpa@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v3 05/35] x86/bugs: Restructure taa mitigation
>
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>
> On Wed, 8 Jan 2025 at 21:27, David Kaplan <david.kaplan@xxxxxxx> wrote:
> > @@ -400,48 +402,71 @@ static void __init taa_select_mitigation(void)
> >                 return;
> >         }
> >
> > -       if (cpu_mitigations_off()) {
> > +       if (cpu_mitigations_off())
> >                 taa_mitigation = TAA_MITIGATION_OFF;
> > -               return;
> > -       }
> >
> >         /*
> >          * TAA mitigation via VERW is turned off if both
> >          * tsx_async_abort=off and mds=off are specified.
> > +        *
> > +        * MDS mitigation will be checked in taa_update_mitigation().
>
> What we are actually talking about here is the new verw_mitigation_enabled(), right?
> I don't think this block/commentary adds any clarity any more. Maybe just delete it?

Yeah, I think that's fair.

Thanks --David Kaplan