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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 9B8E8C433E0 for ; Wed, 17 Mar 2021 13:38:27 +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 2EDB264F4F for ; Wed, 17 Mar 2021 13:38:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EDB264F4F Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=xenproject.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.98701.187355 (Exim 4.92) (envelope-from ) id 1lMWN3-0006st-Ai; Wed, 17 Mar 2021 13:37:57 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 98701.187355; Wed, 17 Mar 2021 13:37:57 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lMWN3-0006sm-5t; Wed, 17 Mar 2021 13:37:57 +0000 Received: by outflank-mailman (input) for mailman id 98701; Wed, 17 Mar 2021 13:37:55 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lMWN1-0006sh-6R for xen-devel@lists.xenproject.org; Wed, 17 Mar 2021 13:37:55 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lMWN1-0006vv-3Y for xen-devel@lists.xenproject.org; Wed, 17 Mar 2021 13:37:55 +0000 Received: from iwj (helo=mariner.uk.xensource.com) by xenbits.xenproject.org with local-bsmtp (Exim 4.92) (envelope-from ) id 1lMWN1-0000Rh-1O for xen-devel@lists.xenproject.org; Wed, 17 Mar 2021 13:37:55 +0000 Received: from iwj by mariner.uk.xensource.com with local (Exim 4.89) (envelope-from ) id 1lMWMx-000219-Sg; Wed, 17 Mar 2021 13:37:51 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xenproject.org; s=20200302mail; h=References:In-Reply-To:Subject:Cc:To:Date :Message-ID:Content-Transfer-Encoding:Content-Type:MIME-Version:From; bh=BdLNvDW7OyxARwrysB3soG4zVUGjI42P1eAMoZYCUTM=; b=Acjh+u1oXFU7AgB6n2TIDGgJGb CdRV+juMMF6p4d1ahpQwjQ2ZIZI+Ztw+GHNpoX/lcexipLIjxGSd9F531WFwn9e4dlxOi7ArAvEnz wxg8X//c9iOCcP4sUZO/oN2+WIDlWHB+c7qkhrtdLq1ktvwIc+YDjxgfIDnrY2yl5dII=; From: Ian Jackson MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <24658.1583.601613.903527@mariner.uk.xensource.com> Date: Wed, 17 Mar 2021 13:37:51 +0000 To: Roger Pau =?iso-8859-1?Q?Monn=E9?= Cc: Xen-devel , Jan Beulich , Andrew Cooper , Wei Liu , Boris Ostrovsky , Ian Jackson Subject: Re: [PATCH 1/3] Revert "x86/msr: drop compatibility #GP handling in guest_{rd,wr}msr()" In-Reply-To: <20210316161844.1658-2-andrew.cooper3@citrix.com> References: <20210316161844.1658-1-andrew.cooper3@citrix.com> <20210316161844.1658-2-andrew.cooper3@citrix.com> X-Mailer: VM 8.2.0b under 24.5.1 (i686-pc-linux-gnu) I have read this thread and with my release manager hat on I feel confused and/or ignorant. Patch 3/ has a good explanation of what the problem is it is addressing and why this is important for 4.15. But then there is Jan's most recent reply starting "I find all of this confusing". Jan, can you please tell me in words of one syllable what the implication of that message is ? In particular is any of what you say a reason for me to withhold my release-ack ? AFAICT there is no explanation for why patches 1/ and 2/ deserve to go into 4.15. We are late in the freeze now, so I would ideally be looking for a clear and compelling argument. I'd also like to understand what the risks are of taking these. Can someone please enlighten me ? Thanks, Ian.