Re: [PATCH v2 2/5] x86/kexec: do unconditional WBINVD in relocate_kernel()

[Huang, Kai]

> > Hi Tom,
> >
> > I am not aware of kexec() support status for SEV-ES/SEV-SNP guests. 
> > Does patch 1 break them?
>
> SNP guests can kexec with some patches that are currently in process 
> around shared to private memory conversions. ES guests can only kexec 
> with a single vCPU. There was a recent patch series to add support for 
> multiple vCPUs.
>
> Patch #1 doesn't break either ES or SNP because we still have an IDT and 
> traditional kernel addressing in place, so the #VC can be handled.

How about plain SEV guest?

> Whereas patch #2 has switched to identity mapping and removed the IDT, 
> so a #VC causes a triple fault.

That makes sense.  Thanks.

Hi Kirill,

Does TDX guest have similar behaviour -- that WBINVD in stop_this_cpu() 
can be handled although it causes #VE, while WBINVD in relocate_kernel() 
will just triple fault the guest?