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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E307FC433F5 for ; Wed, 29 Sep 2021 09:19:45 +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 8D829613A9 for ; Wed, 29 Sep 2021 09:19:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8D829613A9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:58916 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mVVke-0005Cq-KZ for qemu-devel@archiver.kernel.org; Wed, 29 Sep 2021 05:19:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42582) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mVVjk-0003yu-Tc for qemu-devel@nongnu.org; Wed, 29 Sep 2021 05:18:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:43636) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mVVjh-0005PL-UI for qemu-devel@nongnu.org; Wed, 29 Sep 2021 05:18:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632907124; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=S4Vzg/lQG/E/1TPkR1gAKaRWBkCUcowRuyd7xbArqzs=; b=B/6H4p0PnNZyiF6c6c8H7/Ft+j4nAdzyXr9+VQtu5BxuZCJDa9cOykRjn9I5rZqVelZsnm j1HZnCIlSOZJL+tA7Ds9RRGcT45+BME4OvtUUhbR8VN21zvUZweDIRrQBngA4wX9tET21M X1mjEcbrEXrRxyoX+v1KR41tQ9XC1QE= 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-598-6Vi0o-ArNe-5rMGM8R6YAg-1; Wed, 29 Sep 2021 05:18:43 -0400 X-MC-Unique: 6Vi0o-ArNe-5rMGM8R6YAg-1 Received: by mail-wm1-f71.google.com with SMTP id j21-20020a05600c1c1500b0030ccce95837so603633wms.3 for ; Wed, 29 Sep 2021 02:18:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:subject:to:cc:references:from :message-id:date:user-agent:mime-version:in-reply-to :content-transfer-encoding:content-language; bh=S4Vzg/lQG/E/1TPkR1gAKaRWBkCUcowRuyd7xbArqzs=; b=R9KcAddAmyN+438uV9tRY0rG7u7KFcc164AhenzETYcjqMuDxMn75bVlm+jyUxVClr jWCLdCZPDAL3JazBND67pjreMboKDpRbGVu18sHXKFFtdunQfV8Ah5sPWYMguxrzaLAc PeDV68PT1+YvKKXli4OOg7jssddYy6dgcqJzu0mVSKehaibBcnHxWZLr1wCu9Bgjv5EF sgBC0gWZrlVJXMXCHMOYb2reZEidEMgbt1JUA8qFLlgF2pBhULV1g6jnDS6VqcALd1nd JbUypfRlCh4t4o5EHz/GalFUNWSxcwWiMmHZ1YxcKRkUbc2HvR8JBbLRIGn/WfTly+JP ElBg== X-Gm-Message-State: AOAM531Q5ufQUDbFHZPIxJzjiXDH2NFhBZxY0jX9nbHLrj822nhj5hDH FTlFGfpqTIVxqzbYLkMwfDskCzrYkTHgV/Q5b/3XgBcFgl8Bl0VnNDM+xf+HKPR2J8gGRE9yb6D pwbESGak9HhsNh8o= X-Received: by 2002:a5d:4571:: with SMTP id a17mr5379441wrc.290.1632907122210; Wed, 29 Sep 2021 02:18:42 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzzCSKdaJw33ZSjbzUJLavmcew6cEPRE1SVJTcx4QrrdQeDe3kETty0J7swQ/FQ5vtciC8kOg== X-Received: by 2002:a5d:4571:: with SMTP id a17mr5379418wrc.290.1632907122026; Wed, 29 Sep 2021 02:18:42 -0700 (PDT) Received: from ?IPv6:2a01:e0a:59e:9d80:527b:9dff:feef:3874? ([2a01:e0a:59e:9d80:527b:9dff:feef:3874]) by smtp.gmail.com with ESMTPSA id n14sm974344wmc.38.2021.09.29.02.18.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 29 Sep 2021 02:18:41 -0700 (PDT) Subject: Re: [PATCH 0/6] virtio-iommu: Add ACPI support To: Jean-Philippe Brucker References: <20210810084505.2257983-1-jean-philippe@linaro.org> <808699d8-d2cf-bd66-c53d-8ae8c2fdbb9b@redhat.com> From: Eric Auger Message-ID: <0b61d1e3-095e-b830-e160-4f56dd5ff171@redhat.com> Date: Wed, 29 Sep 2021 11:18:39 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eric.auger@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Received-SPF: pass client-ip=170.10.133.124; envelope-from=eric.auger@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-2.562, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: , Reply-To: eric.auger@redhat.com Cc: peter.maydell@linaro.org, ehabkost@redhat.com, mst@redhat.com, richard.henderson@linaro.org, qemu-devel@nongnu.org, shannon.zhaosl@gmail.com, qemu-arm@nongnu.org, pbonzini@redhat.com, imammedo@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi Jean, On 8/27/21 3:30 PM, Jean-Philippe Brucker wrote: > Hi Eric, > > On Tue, Aug 17, 2021 at 04:58:01PM +0200, Eric Auger wrote: >> Hi Jean, >> >> On 8/10/21 10:45 AM, Jean-Philippe Brucker wrote: >>> Allow instantiating a virtio-iommu device on ACPI systems by adding a >>> Virtual I/O Translation table (VIOT). Enable x86 support for VIOT. >> Don't you need your other patch >> "virtio-iommu: Default to bypass during boot"? >> >> Without this latter, for me the guest fails to boot. > Good point, I think I've been lucky during my testing. My bootloader and > kernel are on virtio-blk-pci devices and as I wasn't explicitly enabling > the "iommu_platform" parameter, they would bypass the IOMMU. When enabling > the parameter, boot hangs since the IOMMU isn't enabled when the > bootloader needs to fetch the kernel, and DMA faults. That parameter is > specific to virtio devices. Using another storage for bootloader and > kernel will result in failure to boot. > > I've been postponing the boot-bypass patch since it requires a > specification change to be done right, but it's next on my list. The boot-bypass feature seems a critical feature to overcome the current v3 limitation. Are there big spec changes required? Maybe we shall work on this in parallel of this series because, to me, it will delay the integration of virtio-iommu in libvirt for instance. Thanks Eric > > Thanks, > Jean >