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Date:   Wed, 12 Feb 2020 14:22:20 +0100
From:   Joerg Roedel <joro@8bytes.org>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     x86@kernel.org, hpa@zytor.com, Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Hellstrom <thellstrom@vmware.com>,
        Jiri Slaby <jslaby@suse.cz>,
        Dan Williams <dan.j.williams@intel.com>,
        Tom Lendacky <Thomas.Lendacky@amd.com>,
        Juergen Gross <JGross@suse.com>,
        Kees Cook <keescook@chromium.org>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        Joerg Roedel <jroedel@suse.de>
Subject: Re: [PATCH 50/62] x86/sev-es: Handle VMMCALL Events
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On Tue, Feb 11, 2020 at 04:14:53PM -0800, Andy Lutomirski wrote:
> 
> How about we just don’t do VMMCALL if we’re a SEV-ES guest?  Otherwise
> we add thousands of cycles of extra latency for no good reason.

True, but I left that as a future optimization for now, given the size
the patch-set already has. The idea is to add an abstraction around
VMMCALL for the support code of the various hypervisors and just do a
VMGEXIT in that wrapper when in an SEV-ES guest. But again, that is a
separate patch-set.

Regards,

	Joerg