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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 8B694C282C0 for ; Fri, 25 Jan 2019 11:43:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55B232184B for ; Fri, 25 Jan 2019 11:43:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727749AbfAYLni (ORCPT ); Fri, 25 Jan 2019 06:43:38 -0500 Received: from mail-wm1-f66.google.com ([209.85.128.66]:39374 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbfAYLnh (ORCPT ); Fri, 25 Jan 2019 06:43:37 -0500 Received: by mail-wm1-f66.google.com with SMTP id y8so6312059wmi.4 for ; Fri, 25 Jan 2019 03:43:36 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=lvFku0OL96YmAbhj1sD055gcNlw8rQvCs5uklBfkcFo=; b=RhuMW2g0+EAVgJXhkvtlueMjEC3pUfy8oAHiyUgdVffLoFeScw8c18BLnOPw8bsPD1 t6RjuiyblX8tS5xmXea7GqotLGYViz0IUwGnhS5uj/D4gtFeMpgZzfuvBVlj5NX9sCO9 Q5i45Phul0exexy8ZZzzPQChVTNxT0RsQ/TXA6Lb7v03cQQpp9KRvQHKhtA5ktgg1PAo lpf6bNm1T6W8/r7wRFMx/SX9OvDIyjNGjpc5EI5IjxRSW5pvPgpX0FnQ9le317B9D6HJ 7CSWaHnIUMJa2nIME9GEuaiZPnAQw7SrbaiCTm6grBJVOny7iT9fiG4cn7qpRTHLUJ2h qUDg== X-Gm-Message-State: AJcUukdQ89mW/QiSJJRZRTpbHBHZg68NBMQqT3WChYtLinXa2Rvwa+Gc 0DxfKCfZue65yKYfNOnTFaASRGE8xfIwiw== X-Google-Smtp-Source: ALg8bN6ILADsp9Wp1Z2x8HYAB7dDAYasgddz7NYhPkk4szKvmPUg51mtwr7IZ8+h4pJNYOMYTfOFkA== X-Received: by 2002:a1c:1902:: with SMTP id 2mr6758735wmz.150.1548416615868; Fri, 25 Jan 2019 03:43:35 -0800 (PST) Received: from vitty.brq.redhat.com ([147.229.117.36]) by smtp.gmail.com with ESMTPSA id o3sm80990614wrs.30.2019.01.25.03.43.34 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 25 Jan 2019 03:43:35 -0800 (PST) From: Vitaly Kuznetsov To: kvm@vger.kernel.org Cc: Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Roman Kagan , Liran Alon , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] x86/kvm/hyper-v: recommend using eVMCS only when it is enabled In-Reply-To: <20190125111934.28782-3-vkuznets@redhat.com> References: <20190125111934.28782-1-vkuznets@redhat.com> <20190125111934.28782-3-vkuznets@redhat.com> Date: Fri, 25 Jan 2019 12:43:33 +0100 Message-ID: <87h8dxnesa.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vitaly Kuznetsov writes: > We shouldn't probably be suggesting using Enlightened VMCS when it's not > enabled (not supported from guest's point of view). Hyper-V on KVM seems > to be fine either way but let's be consistent. > Fixes: 2bc39970e932 ("x86/kvm/hyper-v: Introduce KVM_GET_SUPPORTED_HV_CPUID") is missing here. Hope it can be added upon commit. > Reviewed-by: Liran Alon > Signed-off-by: Vitaly Kuznetsov > --- > arch/x86/kvm/hyperv.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index 4840f5b3c88f..4730fcaa70cf 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -1850,7 +1850,8 @@ int kvm_vcpu_ioctl_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid, > ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED; > ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED; > ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED; > - ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED; > + if (evmcs_ver) > + ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED; > > /* > * Default number of spinlock retry attempts, matches -- Vitaly