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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 728B3C433DF for ; Tue, 2 Jun 2020 12:52:48 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 477B820663 for ; Tue, 2 Jun 2020 12:52:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=tklengyel-com.20150623.gappssmtp.com header.i=@tklengyel-com.20150623.gappssmtp.com header.b="NDKDMWTz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 477B820663 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=tklengyel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jg6PF-0002G9-Bt; Tue, 02 Jun 2020 12:52:37 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jg6PE-0002G4-2a for xen-devel@lists.xenproject.org; Tue, 02 Jun 2020 12:52:36 +0000 X-Inumbo-ID: ee1bb83c-a4cf-11ea-81bc-bc764e2007e4 Received: from mail-ed1-x542.google.com (unknown [2a00:1450:4864:20::542]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id ee1bb83c-a4cf-11ea-81bc-bc764e2007e4; Tue, 02 Jun 2020 12:52:35 +0000 (UTC) Received: by mail-ed1-x542.google.com with SMTP id g9so9959276edw.10 for ; Tue, 02 Jun 2020 05:52:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tklengyel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=SC2aYUuLkEh9YWcBjGQ8OFPka9a6woGYTDWf4xa8Aos=; b=NDKDMWTzXVb+QLnEiV03jjuFO19cpEZjFHMvpoJoWQ5lb1vAUJrQ9KrBEQ3fF6j0EM 68rBAfP4WWHnye3+dSXf2iVuNikXqrttD2HWFJuLSBHAkREcoaLR148hHdaNAF8M6qpI 5fcuiPUMHH7RRWPYcmWgwyqV4+K4UFPwpUlP1IElgIdje9YcDsL+5jw1jQfthxIl4yzO RJtqmn28FlD3cgE9UiX2fIMH/dYNZo2pbOJBpermjznuFF5v3GFUEpXdLd6KL9HfXK0f 3XK4Ky3lMdc40YTjKiRnlmQDVBebtN+uhEhEzYSkZES7iQW574qECfPcGGwZRWThmxbr mgKQ== 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:content-transfer-encoding; bh=SC2aYUuLkEh9YWcBjGQ8OFPka9a6woGYTDWf4xa8Aos=; b=NH++/TXZcPN99cx4HJiF6zOOMBVeIHrlz7t3l24/cUCBtxfZqVOvyhEPXnPVMc6sip ND+Ie/4eU3B6LSJc/eE01Xecx+oRcdBRR4lnyFkduhUD3da8g6K71aTxKuM6bBV7wWOW EHxaj4XOO+6VdIRtf40yXJ2NkROrIxMm8EaA7OertwfT3wk+Du0RXyvFCx1K0a9iekq/ bFuDgI8mWCVchwSWt/hAR7syoYqTxUIdXO1nRXyPg5u7lc9JXfaBPMrJEhf9JGhWzvbw yUFNxOB6HRSrYpinqoHzP8rEF/gLbBT4yJtYOqTuyyQhW+TY6Imj/hK7/dgnwoAjTkWe SOuQ== X-Gm-Message-State: AOAM530QuQpULcu/z8nJ9TAljnjEHBV88nwo+eX+XINwCXyow0lRlXhR 9PhzrZvLj1n3iBluHSEkFpJE/RbWBps= X-Google-Smtp-Source: ABdhPJxPOEs0bMsATGINlVeTV4UxcXrqAwa0MbZkd9C9KoK0ZhE558y56dYsOsjBhaBTdECo4FrKgA== X-Received: by 2002:a50:9b13:: with SMTP id o19mr21068354edi.143.1591102354147; Tue, 02 Jun 2020 05:52:34 -0700 (PDT) Received: from mail-wr1-f42.google.com (mail-wr1-f42.google.com. [209.85.221.42]) by smtp.gmail.com with ESMTPSA id d6sm1549054edn.75.2020.06.02.05.52.33 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 02 Jun 2020 05:52:33 -0700 (PDT) Received: by mail-wr1-f42.google.com with SMTP id q11so3313679wrp.3 for ; Tue, 02 Jun 2020 05:52:33 -0700 (PDT) X-Received: by 2002:a5d:490f:: with SMTP id x15mr26040237wrq.259.1591102353002; Tue, 02 Jun 2020 05:52:33 -0700 (PDT) MIME-Version: 1.0 References: <20200602110223.GW1195@Air-de-Roger> In-Reply-To: From: Tamas K Lengyel Date: Tue, 2 Jun 2020 06:51:56 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 for-4.14 1/3] xen/monitor: Control register values To: Jan Beulich Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Petre Pircalabu , Stefano Stabellini , Julien Grall , Wei Liu , Andrew Cooper , Ian Jackson , George Dunlap , Alexandru Isaila , Xen-devel , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On Tue, Jun 2, 2020 at 6:47 AM Jan Beulich wrote: > > On 02.06.2020 14:40, Tamas K Lengyel wrote: > > On Tue, Jun 2, 2020 at 5:08 AM Roger Pau Monn=C3=A9 wrote: > >> > >> On Wed, May 20, 2020 at 08:31:52PM -0600, Tamas K Lengyel wrote: > >>> Extend the monitor_op domctl to include option that enables > >>> controlling what values certain registers are permitted to hold > >>> by a monitor subscriber. > >> > >> I think the change could benefit for some more detail commit message > >> here. Why is this useful? > > > > You would have to ask the Bitdefender folks who made the feature. I > > don't use it. Here we are just making it optional as it is buggy so it > > is disabled by default. > > Now that's exactly the opposite of what I had derived from the > description here so far. Perhaps an at least weak indication > that you want to reword this. For example, from your reply to > Roger I understand it's rather that the new flag allows to > "suppress" the controlling (since presumably you don't change > default behavior), rather then "enabling" it. What we are adding is a domctl you need to call that enables this feature. It's not an option to suppress it. It shouldn't have been enabled by default to begin with. That was a mistake when the feature was contributed and it is buggy. > > >> There already seems to be some support for gating MSR writes, which > >> seems to be expanded by this commit? > > > > We don't expand on any existing features, we make an existing feature o= ptional. > > > >> > >> Is it solving some kind of bug reported? > > > > It does, please take a look at the cover letter. > > Please can such important aspects also go in the commit message, > so they're available later without needing to hunt down mail > threads (besides this way being more readily available to > reviewers)? Noted. Thanks, Tamas