From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [kvm-unit-tests PATCH 1/3] x86/vmx: fix EPT - MMIO access Date: Mon, 3 Jul 2017 13:28:33 -0400 (EDT) Message-ID: <1295348587.13934368.1499102913946.JavaMail.zimbra@redhat.com> References: <20170629172647.22188-1-rkrcmar@redhat.com> <20170629172647.22188-2-rkrcmar@redhat.com> <20170703171343.GB30880@potion> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Cc: Peter Feiner , kvm@vger.kernel.org, David Matlack To: Radim =?utf-8?B?S3LEjW3DocWZ?= Return-path: Received: from mx1.redhat.com ([209.132.183.28]:54566 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754795AbdGCR2f (ORCPT ); Mon, 3 Jul 2017 13:28:35 -0400 In-Reply-To: <20170703171343.GB30880@potion> Sender: kvm-owner@vger.kernel.org List-ID: ----- Original Message ----- > From: "Radim Krčmář" > To: "Paolo Bonzini" > Cc: "Peter Feiner" , kvm@vger.kernel.org, "David Matlack" > Sent: Monday, July 3, 2017 7:13:44 PM > Subject: Re: [kvm-unit-tests PATCH 1/3] x86/vmx: fix EPT - MMIO access > > 2017-06-30 12:22+0200, Paolo Bonzini: > > On 29/06/2017 19:34, Peter Feiner wrote: > > > Reading the memory mapped page with x2apic is a bug. Use the generic > > > reader > > > instead. An alternative would be to disable x2apic. > > > > Disabling x2apic would test what the test is supposed to test. :) > > We should still be doing the same -- we're interested in testing the > MMIO access from the guest, which is being done in ept_main(). > > ept_init_common() is used just to access the reference value and I think > that allowing x2APIC there gives us a bit more leeway, Thanks for the explanation. You're obviously right, will apply tomorrow with an improved commit message. Paolo