Re: [patch v3 31/36] x86/apic: Provide cpu_primary_thread mask

From: Kirill A. Shutemov
Date: Tue May 30 2023 - 07:37:53 EST


On Tue, May 30, 2023 at 12:34:45PM +0200, Thomas Gleixner wrote:
> On Tue, May 30 2023 at 11:26, Thomas Gleixner wrote:
> > On Tue, May 30 2023 at 03:54, Kirill A. Shutemov wrote:
> >> On Mon, May 29, 2023 at 11:31:29PM +0300, Kirill A. Shutemov wrote:
> >>> Disabling parallel bringup helps. I didn't look closer yet. If you have
> >>> an idea let me know.
> >>
> >> Okay, it crashes around .Lread_apicid due to touching MSRs that trigger #VE.
> >>
> >> Looks like the patch had no intention to enable parallel bringup on TDX.
> >>
> >> + * Intel-TDX has a secure RDMSR hypercall, but that needs to be
> >> + * implemented seperately in the low level startup ASM code.
> >>
> >> But CC_ATTR_GUEST_STATE_ENCRYPT that used to filter it out is
> >> SEV-ES-specific thingy and doesn't cover TDX. I don't think we have an
> >> attribute that fits nicely here.
> >
> > Bah. That sucks.
>
> Can we have something consistent in this CC space or needs everything to
> be extra magic per CC variant?

IIUC, CC_ATTR_GUEST_MEM_ENCRYPT should cover all AMD SEV flavours and
Intel TDX. But the name is confusing in this context: memory encryption
has nothing to do with the APIC.

--
Kiryl Shutsemau / Kirill A. Shutemov