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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 384A7C433EF for ; Wed, 20 Jul 2022 17:13:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236867AbiGTRNw (ORCPT ); Wed, 20 Jul 2022 13:13:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230003AbiGTRNt (ORCPT ); Wed, 20 Jul 2022 13:13:49 -0400 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C13E6E89E for ; Wed, 20 Jul 2022 10:13:47 -0700 (PDT) Received: by mail-pf1-x432.google.com with SMTP id 17so6692627pfy.0 for ; Wed, 20 Jul 2022 10:13:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=2iDISCtMujoYb4pXrtkdCn8rbdQJ82HuBDJ0+/zcH90=; b=FH+PekUtFfV6pCGLo8uxIDW9LlIKE8Oj1r0NOE0z9UjfPdJ6jNT52Sw/k7AsmP9Syd c+Nf2wjxnJodwudEymZdXsJGWMO6ZhKl+NFWUK6gugXNnKi806TXU3PO/+0QOMVviOzX NMkCcOkk57XTehSLbxDd6wmgYI9ZH0E3Sqc0BU/3EJk4AHfiNsIUua4pOgZjdiUAgp2o 4UkaLNfp9uWOPEUTOulda8K7Yrn1l/Ij3uwNt4/3El0vpK+19DYn+xo/Le6ddGizayDA y9eZbH14mzK8vrr1Q1Qhc7RFniEVi/CYnspteYo6Q7BJou9yyyg0RUewg2Yks91NNxUI +dcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=2iDISCtMujoYb4pXrtkdCn8rbdQJ82HuBDJ0+/zcH90=; b=f1Ofkg78AF7NydVzVSyG67APG+6/1NlZfH0dytG++MqL7W5UuCpntGkBsQTk0x9s5R R6ekYDXze01bspYPi2/cuCmz47BCJJ7uVr2X/IYs41exuw4CjJ9KSibO0mJquz4uWFno i1BKQtEXpCzqSTTcdi70v2EpXIQx2hsxJeWlUdYSoqto5i9AIEClReKQaklkHAwQNd5K zmTHxAXhFupzjBoVLmbUXuAvkQ7pYAc7n7Rvq1iD5Z1lwt+gkmg0j6XioHybgZTwWL8I BCFVhrvfJzS2CwzTbF6ERPcvJfSKmOG4+sGthESeRhzciduOGbnXSCtxmQYnoQs71lcf /DBg== X-Gm-Message-State: AJIora+wsym9tFdbiGUSloNgFLbPNsp+VN159XiZUqLr/fJatxj+cS5/ 0PiWQALOPZoEG6GOq74PO+u1ZQ== X-Google-Smtp-Source: AGRyM1ukaae49eieQG9eqzW9jOyZthb7CjGb22iyaiJSCFelzdR6Ij6IZfypk2lJdDbeFNT43k1yrQ== X-Received: by 2002:aa7:870b:0:b0:522:c223:5c5e with SMTP id b11-20020aa7870b000000b00522c2235c5emr40260065pfo.6.1658337226778; Wed, 20 Jul 2022 10:13:46 -0700 (PDT) Received: from google.com (123.65.230.35.bc.googleusercontent.com. [35.230.65.123]) by smtp.gmail.com with ESMTPSA id h14-20020a63e14e000000b004161b3c3388sm12108750pgk.26.2022.07.20.10.13.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Jul 2022 10:13:46 -0700 (PDT) Date: Wed, 20 Jul 2022 17:13:42 +0000 From: Sean Christopherson To: Kechen Lu Cc: kvm@vger.kernel.org, pbonzini@redhat.com, vkuznets@redhat.com, somduttar@nvidia.com, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v3 3/7] KVM: x86: Reject disabling of MWAIT interception when not allowed Message-ID: References: <20220615011622.136646-1-kechenl@nvidia.com> <20220615011622.136646-4-kechenl@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220615011622.136646-4-kechenl@nvidia.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 14, 2022, Kechen Lu wrote: > From: Sean Christopherson > > Reject KVM_CAP_X86_DISABLE_EXITS if userspace attempts to disable MWAIT > exits and KVM previously reported (via KVM_CHECK_EXTENSION) that MWAIT is > not allowed in guest, e.g. because it's not supported or the CPU doesn't > have an aways-running APIC timer. > > Fixes: 4d5422cea3b6 ("KVM: X86: Provide a capability to disable MWAIT intercepts") > Signed-off-by: Sean Christopherson > --- > arch/x86/kvm/x86.c | 21 ++++++++++++++------- > 1 file changed, 14 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index b419b258ed90..f31ebbb1b94f 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -4199,6 +4199,17 @@ static inline bool kvm_can_mwait_in_guest(void) > boot_cpu_has(X86_FEATURE_ARAT); > } > > +static u64 kvm_get_allowed_disable_exits(void) > +{ > + u64 r = KVM_X86_DISABLE_EXITS_HLT | KVM_X86_DISABLE_EXITS_PAUSE | > + KVM_X86_DISABLE_EXITS_CSTATE; > + > + if(kvm_can_mwait_in_guest()) Probably my fault for not fixing this during copy+paste, but add a space after the if, i.e. if (kvm_can_mwait_in_guest()) > + r |= KVM_X86_DISABLE_EXITS_MWAIT; > + > + return r; > +}