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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 9982DC2BA83 for ; Thu, 13 Feb 2020 11:49:00 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 72335217F4 for ; Thu, 13 Feb 2020 11:49:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 72335217F4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51022 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j2CzL-0004NV-M8 for qemu-devel@archiver.kernel.org; Thu, 13 Feb 2020 06:48:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34677) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j2CxW-0003RT-Gv for qemu-devel@nongnu.org; Thu, 13 Feb 2020 06:47:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j2CxU-0004vs-Nk for qemu-devel@nongnu.org; Thu, 13 Feb 2020 06:47:06 -0500 Received: from 3.mo178.mail-out.ovh.net ([46.105.44.197]:49549) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j2CxT-0004tR-E5 for qemu-devel@nongnu.org; Thu, 13 Feb 2020 06:47:04 -0500 Received: from player697.ha.ovh.net (unknown [10.110.171.5]) by mo178.mail-out.ovh.net (Postfix) with ESMTP id 767AF8C80A for ; Thu, 13 Feb 2020 12:47:00 +0100 (CET) Received: from kaod.org (lns-bzn-46-82-253-208-248.adsl.proxad.net [82.253.208.248]) (Authenticated sender: groug@kaod.org) by player697.ha.ovh.net (Postfix) with ESMTPSA id 365D5F56DB9D; Thu, 13 Feb 2020 11:46:45 +0000 (UTC) Date: Thu, 13 Feb 2020 12:46:43 +0100 From: Greg Kurz To: David Gibson Subject: Re: [PATCH v2 0/2] spapr: Use vIOMMU translation for virtio by default Message-ID: <20200213124643.7b205d44@bahia.lan> In-Reply-To: <20200213005837.131791-1-david@gibson.dropbear.id.au> References: <20200213005837.131791-1-david@gibson.dropbear.id.au> X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Ovh-Tracer-Id: 3977522897199536614 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedugedrieekgdefudcutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpeffhffvuffkjghfofggtgfgsehtjeertdertddvnecuhfhrohhmpefirhgvghcumfhurhiiuceoghhrohhugheskhgrohgurdhorhhgqeenucffohhmrghinheprhgvughhrghtrdgtohhmnecukfhppedtrddtrddtrddtpdekvddrvdehfedrvddtkedrvdegkeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhhouggvpehsmhhtphdqohhuthdphhgvlhhopehplhgrhigvrheileejrdhhrgdrohhvhhdrnhgvthdpihhnvghtpedtrddtrddtrddtpdhmrghilhhfrhhomhepghhrohhugheskhgrohgurdhorhhgpdhrtghpthhtohepqhgvmhhuqdguvghvvghlsehnohhnghhnuhdrohhrgh X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 46.105.44.197 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pair@us.ibm.com, mst@redhat.com, aik@ozlabs.ru, qemu-devel@nongnu.org, qemu-ppc@nongnu.org, clg@kaod.org, mdroth@us.ibm.com, paulus@samba.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 13 Feb 2020 11:58:35 +1100 David Gibson wrote: > Upcoming Secure VM support for pSeries machines introduces some > complications for virtio, since the transfer buffers need to be > explicitly shared so that the hypervisor can access them. > > While it's not strictly speaking dependent on it, the fact that virtio > devices bypass normal platform IOMMU translation complicates the issue > on the guest side. Since there are some significan downsides to > bypassing the vIOMMU anyway, let's just disable that. > > There's already a flag to do this in virtio, just turn it on by > default for forthcoming pseries machine types. > > Any opinions on whether dropping support for the older guest kernels > is acceptable at this point? > As expected, this breaks compatibility with existing RHEL 6.10 guests. Each patch in this series requires an extra -global option to be specified on the command line in order to boot successfully. Patch 1: -global virtio-pci.disable-legacy=auto Patch 2: -global virtio-pci.iommu_platform=off As seen on the RH site [1], RHEL6 will reach "End of Maintenance Support or Maintenance Support 2 (Product retirement)" on November 30, 2020 and "End of Extended Life-cycle Support" on June 30, 2024. Not sure if it's okay to drop support for RHEL6 this soon. RHEL 7.7 guests seem to be unaffected. [1] https://access.redhat.com/support/policy/updates/errata/#Life_Cycle_Dates > Changes since v1: > * Added information on which guest kernel versions will no longer > work with these changes > * Use Michael Tsirkin's suggested better way of handling the machine > type change > > David Gibson (2): > spapr: Disable legacy virtio devices for pseries-5.0 and later > spapr: Enable virtio iommu_platform=on by default > > hw/ppc/spapr.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) >