Re: [PATCH v3 70/75] x86/head/64: Setup TSS early for secondary CPUs

From: Borislav Petkov
Date: Tue Jun 02 2020 - 11:46:19 EST


On Tue, Apr 28, 2020 at 05:17:20PM +0200, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> The #VC exception will trigger very early in head_64.S, when the first
> CPUID instruction is executed. When secondary CPUs boot, they already
> load the real system IDT, which has the #VC handler configured to be
> using an IST stack. IST stacks require a TSS to be loaded, to set up the
> TSS early for bringing up the secondary CPUs. Use the RW version of
> early, until cpu_init() switches to the RO mapping.

I think you wanna say "Use the read-write version of the per-CPU TSS struct
early." here.

--
Regards/Gruss,
Boris.

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