On Tue, Apr 28, 2020 at 05:17:20PM +0200, Joerg Roedel wrote:

From: Joerg Roedel <redacted>

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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