From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753356Ab0G0Sco (ORCPT ); Tue, 27 Jul 2010 14:32:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11324 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751810Ab0G0Scn (ORCPT ); Tue, 27 Jul 2010 14:32:43 -0400 Message-ID: <4C4F2643.8080507@redhat.com> Date: Tue, 27 Jul 2010 21:32:35 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.7) Gecko/20100720 Fedora/3.1.1-1.fc13 Thunderbird/3.1.1 MIME-Version: 1.0 To: Joerg Roedel CC: Marcelo Tosatti , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] KVM: SVM: Emulate next_rip svm feature References: <1280247261-19115-1-git-send-email-joerg.roedel@amd.com> <1280247261-19115-3-git-send-email-joerg.roedel@amd.com> In-Reply-To: <1280247261-19115-3-git-send-email-joerg.roedel@amd.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/27/2010 07:14 PM, Joerg Roedel wrote: > This patch implements the emulations of the svm next_rip > feature in the nested svm implementation in kvm. > > Signed-off-by: Joerg Roedel > --- > arch/x86/kvm/svm.c | 8 +++++++- > 1 files changed, 7 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index 7d10f2c..b44c9cc 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -1919,6 +1919,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm) > nested_vmcb->control.exit_info_2 = vmcb->control.exit_info_2; > nested_vmcb->control.exit_int_info = vmcb->control.exit_int_info; > nested_vmcb->control.exit_int_info_err = vmcb->control.exit_int_info_err; > + nested_vmcb->control.next_rip = vmcb->control.next_rip; > Can it be really this simple? Suppose we emulate a nested guest instruction just before vmexit, doesn't that invalidate vmcb->control.next_rip? Can that happen? -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.