From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 70E1EC10F12 for ; Mon, 15 Apr 2019 19:14:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 378762075B for ; Mon, 15 Apr 2019 19:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355698; bh=LPYxgzrjn3gUx1Pjhl0CVwF+Ip40X+EZsm37eXdbZow=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=X1Bxe9c7H6YQzAS4xkzrzFBxEwHspZ/SiRWoqYiMBRm9aoLZO4mBel4R7ZKWH5Uea jHh4fp5+1Ce7dxkar+SKo7TsTO5nZNu0I6Q0e1NRWtPn8cEE9GFhC2iCcOHzVz1o3Q 0D4k2JE9ppLNUDN/juQ9mrYExawUOfGfPOd3CsnU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731811AbfDOTO4 (ORCPT ); Mon, 15 Apr 2019 15:14:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:52738 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731765AbfDOTOc (ORCPT ); Mon, 15 Apr 2019 15:14:32 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 88B9D2075B; Mon, 15 Apr 2019 19:14:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355672; bh=LPYxgzrjn3gUx1Pjhl0CVwF+Ip40X+EZsm37eXdbZow=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ft+7RJjBX4wcipEroowCQHYbXRbBa8ld2k5psVKUO6cRd9Q479zyFC0iMYyeWC4rf /tpYS+EUNOA+hF6UcvfP0L+4Ewj07USyDQKB2buUqz6qB4aX7PYQVccKTBcyT2aEID KAmEOLyfHYa5+Qdd0KU7lLDVx+HX8B5j3BQLGJXE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Orr , Jim Mattson , Paolo Bonzini Subject: [PATCH 5.0 116/117] KVM: x86: nVMX: fix x2APIC VTPR read intercept Date: Mon, 15 Apr 2019 21:01:26 +0200 Message-Id: <20190415183750.654071873@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183744.887851196@linuxfoundation.org> References: <20190415183744.887851196@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marc Orr commit c73f4c998e1fd4249b9edfa39e23f4fda2b9b041 upstream. Referring to the "VIRTUALIZING MSR-BASED APIC ACCESSES" chapter of the SDM, when "virtualize x2APIC mode" is 1 and "APIC-register virtualization" is 0, a RDMSR of 808H should return the VTPR from the virtual APIC page. However, for nested, KVM currently fails to disable the read intercept for this MSR. This means that a RDMSR exit takes precedence over "virtualize x2APIC mode", and KVM passes through L1's TPR to L2, instead of sourcing the value from L2's virtual APIC page. This patch fixes the issue by disabling the read intercept, in VMCS02, for the VTPR when "APIC-register virtualization" is 0. The issue described above and fix prescribed here, were verified with a related patch in kvm-unit-tests titled "Test VMX's virtualize x2APIC mode w/ nested". Signed-off-by: Marc Orr Reviewed-by: Jim Mattson Fixes: c992384bde84f ("KVM: vmx: speed up MSR bitmap merge") Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx/nested.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -578,7 +578,7 @@ static inline bool nested_vmx_prepare_ms nested_vmx_disable_intercept_for_msr( msr_bitmap_l1, msr_bitmap_l0, X2APIC_MSR(APIC_TASKPRI), - MSR_TYPE_W); + MSR_TYPE_R | MSR_TYPE_W); if (nested_cpu_has_vid(vmcs12)) { nested_vmx_disable_intercept_for_msr(