From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754637AbaBRJSe (ORCPT ); Tue, 18 Feb 2014 04:18:34 -0500 Received: from mail-ee0-f42.google.com ([74.125.83.42]:34811 "EHLO mail-ee0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754030AbaBRJSb (ORCPT ); Tue, 18 Feb 2014 04:18:31 -0500 Message-ID: <5303255D.8000501@redhat.com> Date: Tue, 18 Feb 2014 10:18:21 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , linux-kernel@vger.kernel.org CC: kvm@vger.kernel.org, joro@8bytes.org, stable@vger.kernel.org Subject: Re: [PATCH] KVM: SVM: fix NMI window after iret References: <1389988362-15260-1-git-send-email-rkrcmar@redhat.com> In-Reply-To: <1389988362-15260-1-git-send-email-rkrcmar@redhat.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 17/01/2014 20:52, Radim Krčmář ha scritto: > We should open NMI window right after an iret, but SVM exits before it. > We wanted to single step using the trap flag and then open it. > (or we could emulate the iret instead) > We don't do it since commit 3842d135ff2 (likely), because the iret exit > handler does not request an event, so NMI window remains closed until > the next exit. > > Fix this by making KVM_REQ_EVENT request in the iret handler. > > Signed-off-by: Radim Krčmář > --- > (btw. kvm-unit-tests weren't executed on SVM since Nov 2010, at least) > > arch/x86/kvm/svm.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index c7168a5..b5a735b 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -2829,6 +2829,7 @@ static int iret_interception(struct vcpu_svm *svm) > clr_intercept(svm, INTERCEPT_IRET); > svm->vcpu.arch.hflags |= HF_IRET_MASK; > svm->nmi_iret_rip = kvm_rip_read(&svm->vcpu); > + kvm_make_request(KVM_REQ_EVENT, &svm->vcpu); > return 1; > } > > Applying to kvm/queue, thanks. Paolo