Re: [Question PATCH kernel] x86/amd/sev/nmi+vc: Fix stack handling (why is this happening?)

[Joerg Roedel]

On Tue, Jan 31, 2023 at 03:53:39PM +0000, Sean Christopherson wrote:
> I don't think that is technically true.  A _well-behaved_ hypervisor will not
> intercept DR0-DR6 accesses for SEV-ES guests, but AFAICT nothing in the SEV-ES
> architecture enforces that behavior.

Not from the hardware architecture side, but the GHCB spec does not
list NAE events for DR0-DR6 accesses, so a guest is not required to
handle them in the VC handler.

Linux under SEV-ES will crash if the HV intercepts debug registers,
except DR7.

Regards,

	Joerg