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=-8.3 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 24448C31E45 for ; Thu, 13 Jun 2019 17:36:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF78921911 for ; Thu, 13 Jun 2019 17:36:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="WMxpmd17" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727071AbfFMRgW (ORCPT ); Thu, 13 Jun 2019 13:36:22 -0400 Received: from mail-io1-f68.google.com ([209.85.166.68]:40198 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725616AbfFMRgV (ORCPT ); Thu, 13 Jun 2019 13:36:21 -0400 Received: by mail-io1-f68.google.com with SMTP id n5so18780648ioc.7 for ; Thu, 13 Jun 2019 10:36:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wuyZxNfgrI7BM+E+ydWJGlXujwTzOschBVbnlzkKX0I=; b=WMxpmd17td2/uZVkrQ11LSHO6aGT4MeYtJ3LToPljmZu085pzyCNyQz3yFsPk6m88c PU7JjCLNDqaLB+h6c5n12fZPks+X17B2TNVzQaSeBz4ZdtwSpBRSxqjB4fGwdZYTKj3a 4BA+H0yQgU7gNc0kDRsTSZ8iWMKStcOtlZxIKc2HE+ci29O6wDGAZpyYsZlwO3/0bArZ mEcyaadhF5+0AcEBEdAN39AjKDTnt4nxWXSg2Ni/6CyjmMaxHC6f512+4tRciRolfY90 9yJ1GDnHvyNYAN6n3DPi0za4hc105E14Sic8E1mHxNLJzfEk4U0T2+c7ikBl8RnL1ZcU 2bHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wuyZxNfgrI7BM+E+ydWJGlXujwTzOschBVbnlzkKX0I=; b=VBLhk6pr2R4nqFFIYA52ckjjA1x7OEii27MYiHvNy9Mp4c8jTr3R1jXlZmVwWB4+O9 iKvNxaQK60TF5n1aQAyePEpRtLbk9jJia+jH5RGWimJpXixIvp+ZYd80ype1C3GC68V7 XNkrR4yzMvY9SIrep1gazKphyvCcg1dbOrww7Yum04snN51oyDM+Q1nDL5XPF75Q+uol g2mGEdIy5hZkBhrUCtdoBcB9DTTTzINayj8j3sCdc3k/fvRDJiegMIR8tpQ8jSbHHLup ugPlwDC6pMLw5q+EhC/noIJImdcOx4YT0228HdYMmo7ZithM0kYtxUVbMA2UtBR0FVfQ vKbQ== X-Gm-Message-State: APjAAAX8PhA08JI0PC4S209q0KbboCrdfLeKNlGXFjnn01+WbI3SKavE jR638sYBDwQ1ubYYQh39sYJkE8bXzZ3cz3oToN3asQ== X-Google-Smtp-Source: APXvYqyPB3Kyskq7hut+OLgzxHcWQ80LiIMDj7RRGsc1Ky50UShxrRDQfPiXKyT0DlmGxqY589dhPuXBDrk3PDLKwPI= X-Received: by 2002:a02:781c:: with SMTP id p28mr61530969jac.31.1560447380886; Thu, 13 Jun 2019 10:36:20 -0700 (PDT) MIME-Version: 1.0 References: <20190507153629.3681-1-sean.j.christopherson@intel.com> <20190507153629.3681-2-sean.j.christopherson@intel.com> <9d82caf7-1735-a5e8-8206-bdec3ddf12d4@redhat.com> In-Reply-To: <9d82caf7-1735-a5e8-8206-bdec3ddf12d4@redhat.com> From: Jim Mattson Date: Thu, 13 Jun 2019 10:36:09 -0700 Message-ID: Subject: Re: [PATCH 1/7] KVM: nVMX: Intercept VMWRITEs to read-only shadow VMCS fields To: Paolo Bonzini Cc: Sean Christopherson , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , kvm list , Liran Alon Content-Type: text/plain; charset="UTF-8" Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Jun 13, 2019 at 10:18 AM Paolo Bonzini wrote: > Also, while this may vary dynamically based on the L2 guest that is > running, this is much less true for unrestricted-guest processors. > Without data on _which_ scenarios are bad for a static set of shadowed > fields, I'm not really happy to add even more complexity. Data supporting which scenarios would lead you to entertain more complexity? Is it even worth collecting data on L3 performance, for example? :-)