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_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8982EC04AB3 for ; Wed, 29 May 2019 05:38:00 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 38962217D9 for ; Wed, 29 May 2019 05:38:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="C4C0DC66" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 38962217D9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:47548 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hVrHj-0005Qa-7q for qemu-devel@archiver.kernel.org; Wed, 29 May 2019 01:37:59 -0400 Received: from eggs.gnu.org ([209.51.188.92]:60618) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hVrGq-0004zt-8e for qemu-devel@nongnu.org; Wed, 29 May 2019 01:37:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hVrGp-0001Ur-Cb for qemu-devel@nongnu.org; Wed, 29 May 2019 01:37:04 -0400 Received: from mail-wr1-x442.google.com ([2a00:1450:4864:20::442]:41697) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hVqsR-0001yg-In for qemu-devel@nongnu.org; Wed, 29 May 2019 01:11:51 -0400 Received: by mail-wr1-x442.google.com with SMTP id c2so640039wrm.8 for ; Tue, 28 May 2019 22:11:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=YQ1xqtLZLWliwP7boBDEU6TpsqPaCpy6byNYhOdb2C4=; b=C4C0DC66zbqFpcUQlBc5YjPXXPtAnIyTQdNY6+aiN7kIBLhH6z5EbTV7iRVf5zWH1g xwL2/e+QLn7AOZkDhP9PC/GM10F04W/7kPQ8twB5G9YJ4d7NlQXy3AahDh1dNPK8KpXp u2+Fb4P2WhSQOzcNFu2SA3vH0VVK2zUvfZyu/+Mx+gQSS1f3HjdXQlc0bt7nrAvqyB3+ fupLb+puKY0tylSVjtGQGrrNPL2QAnpe3AKaDV3T9vX+HPr5T3QI0361pK1O8vP4I04w sHZC2Wc9Y5kdaSuv+OL7BwCj1qo2fQz24Z2bOAyvMtbusZoCEo/F2pcgb7sM15zPHcd9 wDxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=YQ1xqtLZLWliwP7boBDEU6TpsqPaCpy6byNYhOdb2C4=; b=myBsbYXpVG1kMR0HXZCXVnjNiRxYr1PQnnOnrAoFEJ61DsOaWeP3fUSFHW/wwRUE2t EIQb1wR5fmYBajk6O2oYWUnsIVP4OZP0uDwmfglUbebkhjlzukwwIg+bevo/9hBr7kyZ HyS+U2Epcvane2kAtCLh5QkRQNMYxQtlycriSdl3S/JpG86/AGUxPHGKfUpB8ukm21Zr bNsrFXnuwIC5zLBtmXqGEtxnCr63vfx07H55tWtAlGW9lZbiy6bpudtem2X962VaqkaW HtWBhq9qzhVT6DG2F6NNaoSCvg94sqTRI6jyvYMRhXcflv/sgTw+8d9+mlf8SpT8G/cs s/7g== X-Gm-Message-State: APjAAAW5K3scKbir9yi3m98o9RrCOFFPCjLRN+FcFdoc5QFsMIsfHWxR gHa1EXiQjybhrxokqa+x0y0= X-Google-Smtp-Source: APXvYqwmeC85rd4jOv7WEsQPzP2f3P7214UFSu7k/fHLdKjn5jbnPLsd3cle4G+PyO5/qZ8O8Jt8Yw== X-Received: by 2002:a5d:6207:: with SMTP id y7mr58368955wru.265.1559106698898; Tue, 28 May 2019 22:11:38 -0700 (PDT) Received: from localhost.localdomain ([37.142.144.27]) by smtp.gmail.com with ESMTPSA id u19sm12434321wmu.41.2019.05.28.22.11.37 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Tue, 28 May 2019 22:11:38 -0700 (PDT) To: Gerd Hoffmann References: <20190528204331.5280-1-kraxel@redhat.com> <016bde36-9476-91c3-0a06-5cd13d317083@gmail.com> <20190529050123.dblwhfffwa5emhjf@sirius.home.kraxel.org> From: Marcel Apfelbaum Message-ID: Date: Wed, 29 May 2019 08:11:36 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190529050123.dblwhfffwa5emhjf@sirius.home.kraxel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: No matching host in p0f cache. That's all we know. X-Received-From: 2a00:1450:4864:20::442 Subject: Re: [Qemu-devel] [PATCH] q35: fix mmconfig and PCI0._CRS X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , qemu-devel@nongnu.org, Paolo Bonzini , Igor Mammedov , =?UTF-8?B?TMOhc3psw7Mgw4lyc2Vr?= , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi Gerd, On 5/29/19 8:01 AM, Gerd Hoffmann wrote: > On Wed, May 29, 2019 at 07:48:03AM +0300, Marcel Apfelbaum wrote: >> Hi Gerd, >> >> On 5/28/19 11:43 PM, Gerd Hoffmann wrote: >>> This patch changes the handling of the mmconfig area. Thanks to the >>> pci(e) expander devices we already have the logic to exclude address >>> ranges from PCI0._CRS. We can simply add the mmconfig address range >>> to the list get it excluded as well. >>> >>> With that in place we can go with a fixed pci hole which covers the >>> whole area from the end of (low) ram to the ioapic. >>> >>> This will make the whole logic alot less fragile. No matter where the >>> firmware places the mmconfig xbar, things should work correctly. The >>> guest also gets a bit more PCI address space (seabios boot): >>> >>> # cat /proc/iomem >>> [ ... ] >>> 7ffdd000-7fffffff : reserved >>> 80000000-afffffff : PCI Bus 0000:00 <<-- this is new >>> b0000000-bfffffff : PCI MMCONFIG 0000 [bus 00-ff] >>> b0000000-bfffffff : reserved >>> c0000000-febfffff : PCI Bus 0000:00 >>> f8000000-fbffffff : 0000:00:01.0 >>> [ ... ] >>> >>> So this is a guest visible change. >> Looks good to me, but shouldn't we use some compat >> property to not affect previous machine versions? > acpi table changes are typically not versioned, and IIRC the acpi tables > are part of the live migration data stream so the tables will not change > under the feet of the running guest even when it is migrated to another > qemu version. I wasn't "worried" only about migration, but also about the visible change in the guests keeping the same machine type and upgrading QEMU. I am not saying is a "big" issue since it will probably not affect the guests at all. Upgrading QEMU will look like a firmware update or something. Thanks, Marcel > cheers, > Gerd >