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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 1B091C2D0DB for ; Mon, 20 Jan 2020 16:33:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E40F62087E for ; Mon, 20 Jan 2020 16:33:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="jMrUkcJn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729016AbgATQdc (ORCPT ); Mon, 20 Jan 2020 11:33:32 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:23756 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726901AbgATQdb (ORCPT ); Mon, 20 Jan 2020 11:33:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579538010; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=K1zcq54gP0pXiBRG1fF2BRNY1nGBgHmf0naqBgZVYZA=; b=jMrUkcJnmYqziVQeI1QHaidzwzvXfmAPLJ2K1rS+HH3nTNQyIGddrkL7VPbI2q/3LVOrfO C23SQyCJq5I405s196qRrJQDIdSlPcaydjyKLOGclP2nPvQEZLDTq0Gm8v9yG8IeSW2qnL s4qdOZUEZRcJXrM9ao0A2ufkgTBYwdA= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-222-wS97HA4xMU2QUXuCm0_H8g-1; Mon, 20 Jan 2020 11:33:29 -0500 X-MC-Unique: wS97HA4xMU2QUXuCm0_H8g-1 Received: by mail-wm1-f71.google.com with SMTP id 18so11195wmp.0 for ; Mon, 20 Jan 2020 08:33:29 -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=K1zcq54gP0pXiBRG1fF2BRNY1nGBgHmf0naqBgZVYZA=; b=VuxS++R4xmTZdCSCONvgXjE9oy3DIU503jiHnwUmZITw11VVPZ9wZdTyRxtVCTvSjx xk0b0nouajCEYDi9bK+QfWqmP+mDbe+u90DRmaB08/gObdaFQ+oXc4vjSZWiYMryc0V2 91lLg6IK40NHWpCyWX3mOnzt59vTmnIeSFofp7u4ABp2GDbB1NJXr9YjeO1MMIFvKGIA iiHWxEYLIB+0OLuvRzTxc1E/io+IVhVUhpgZYn1ZxxrWvLf3oF+5q/Sil1KFsAnHp6/h eaj2jbNNLcDtNDWOgK/B/TlNK+cB/kHxcCH4NeI840AwXW7eUZclFkkPVm/gesnf7j7N eJnA== X-Gm-Message-State: APjAAAU3eRpkmifOazpBSEo1I+Iyx8Kje61U4gqxDTNneeOvQUgUhp8Y M5DCQWShr3MuttJCBngexVsBs5xATG10Z0qFiTexYBPhpT4odcPmHEaYBO2hrAklL3vMmG+aHdd uKMMidbToN0GZ X-Received: by 2002:a5d:45c4:: with SMTP id b4mr298155wrs.303.1579538008686; Mon, 20 Jan 2020 08:33:28 -0800 (PST) X-Google-Smtp-Source: APXvYqyH1y6QHBvoU2MiBx+BCIkxLVbqTXcXlc6sAqVsfOSnE//yyWWeKTqmGdEFekqNwtFNoZ6hIw== X-Received: by 2002:a5d:45c4:: with SMTP id b4mr298137wrs.303.1579538008452; Mon, 20 Jan 2020 08:33:28 -0800 (PST) Received: from vitty.brq.redhat.com (nat-pool-brq-t.redhat.com. [213.175.37.10]) by smtp.gmail.com with ESMTPSA id v22sm22281449wml.11.2020.01.20.08.33.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Jan 2020 08:33:27 -0800 (PST) From: Vitaly Kuznetsov To: Paolo Bonzini Cc: Jim Mattson , Sean Christopherson , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Liran Alon Subject: Re: [RFC] Revert "kvm: nVMX: Restrict VMX capability MSR changes" In-Reply-To: <30525d58-10de-abb4-8dad-228da766ff82@redhat.com> References: <20200120151141.227254-1-vkuznets@redhat.com> <30525d58-10de-abb4-8dad-228da766ff82@redhat.com> Date: Mon, 20 Jan 2020 17:33:26 +0100 Message-ID: <87k15mf5pl.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Paolo Bonzini writes: > On 20/01/20 16:11, Vitaly Kuznetsov wrote: >> >> RFC. I think the check for vmx->nested.vmxon is legitimate for everything >> but restore so removing it (what I do with the revert) is likely a no-go. >> I'd like to gather opinions on the proper fix: should we somehow check >> that the vCPU is in 'restore' start (has never being run) and make >> KVM_SET_MSRS pass or should we actually mandate that KVM_SET_NESTED_STATE >> is run after KVM_SET_MSRS by userspace? >> >> Signed-off-by: Vitaly Kuznetsov > > I think this should be fixed in QEMU, by doing KVM_SET_MSRS for feature > MSRs way earlier. I'll do it since I'm currently working on a patch to > add a KVM_SET_MSR for the microcode revision. Works for me, thanks) The bigger issue is that the vCPU setup sequence (like QEMU's kvm_arch_put_registers()) effectively becomes an API convention and as it gets more complex it would be great to document it for KVM. -- Vitaly