From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754847AbdDMQjn (ORCPT ); Thu, 13 Apr 2017 12:39:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52804 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753811AbdDMQjl (ORCPT ); Thu, 13 Apr 2017 12:39:41 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 4C898C057FA7 Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=rkrcmar@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 4C898C057FA7 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini Subject: [PATCH] KVM: nVMX: fix AD condition when handling EPT violation Date: Thu, 13 Apr 2017 18:39:18 +0200 Message-Id: <20170413163918.5830-1-rkrcmar@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Thu, 13 Apr 2017 16:39:41 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I have introduced this bug when applying and simplifying Paolo's patch as we agreed on the list. The original was "x &= ~y; if (z) x |= y;". Here is the story of a bad workflow: A maintainer was already testing with the intended change, but it was applied only to a testing repo on a different machine. When the time to push tested patches to kvm/next came, he realized that this change was missing and quickly added it to the maintenance repo, didn't test again (because the change is trivial, right), and pushed the world to fire. Fixes: ae1e2d1082ae ("kvm: nVMX: support EPT accessed/dirty bits") Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index cfdb0d9389d1..837f6dd1ae9c 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6221,7 +6221,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu) * page table accesses are reads or writes. */ u64 eptp = nested_ept_get_cr3(vcpu); - if (eptp & VMX_EPT_AD_ENABLE_BIT) + if (!(eptp & VMX_EPT_AD_ENABLE_BIT)) exit_qualification &= ~EPT_VIOLATION_ACC_WRITE; } -- 2.12.0