Re: [tip: x86/seves] x86/vmware: Add VMware-specific handling for VMMCALL under SEV-ES

From: Joerg Roedel
Date: Wed Oct 28 2020 - 21:23:26 EST


On Tue, Oct 27, 2020 at 04:19:45PM -0700, Erdem Aktas wrote:
> Looking at the VMWARE_VMCALL(cmd, eax, ebx, ecx, edx) definition, it
> seems to me only 4 registers are required to be shared with
> hypervisor. I don't know much about vmware but is not
> vmware_sev_es_hcall_prepare expose more registers than needed and also
> vmware_sev_es_hcall_finish might let the hypvervisor to modify
> additional registers which are not used?
>
> Just checking if this is intentional and what I am missing here.

Original patch is from Doug, maybe he can clarify what needs to be
shared. I only adapted it to the call-backs.

Doug?

Regards,

Joerg