Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756436AbdGKSfk (ORCPT ); Tue, 11 Jul 2017 14:35:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60983 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756057AbdGKSfi (ORCPT ); Tue, 11 Jul 2017 14:35:38 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com E18D14E34E Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bsd@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com E18D14E34E From: Bandan Das To: Jim Mattson Cc: David Hildenbrand , kvm list , Paolo Bonzini , LKML Subject: Re: [PATCH v4 3/3] KVM: nVMX: Emulate EPTP switching for the L1 hypervisor References: <20170710204936.4001-1-bsd@redhat.com> <20170710204936.4001-4-bsd@redhat.com> <2d50ebc4-9328-ce08-b55b-6a331ee13cc3@redhat.com> Date: Tue, 11 Jul 2017 14:35:00 -0400 In-Reply-To: (Jim Mattson's message of "Tue, 11 Jul 2017 11:22:37 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 11 Jul 2017 18:35:38 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 671 Lines: 18 Jim Mattson writes: ... >>> I can find the definition for an vmexit in case of index >= >>> VMFUNC_EPTP_ENTRIES, but not for !vmcs12->eptp_list_address in the SDM. >>> >>> Can you give me a hint? >> >> I don't think there is. Since, we are basically emulating eptp switching >> for L2, this is a good check to have. > > There is nothing wrong with a hypervisor using physical page 0 for > whatever purpose it likes, including an EPTP list. Right, but of all the things, a l1 hypervisor wanting page 0 for a eptp list address most likely means it forgot to initialize it. Whatever damage it does will still end up with vmfunc vmexit anyway. Bandan