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 F0DA7C433EF for ; Tue, 2 Nov 2021 12:10:36 +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 973ED60F24 for ; Tue, 2 Nov 2021 12:10:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 973ED60F24 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]:49190 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mhscd-0004Tu-Pm for qemu-devel@archiver.kernel.org; Tue, 02 Nov 2021 08:10:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46814) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhroF-0005xE-AG for qemu-devel@nongnu.org; Tue, 02 Nov 2021 07:18:31 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:30728) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhroB-0004tt-QD for qemu-devel@nongnu.org; Tue, 02 Nov 2021 07:18:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635851906; h=from:from: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=XXCD/y+EIIpD27UrY6lZoLmfoZFyT8+831AZbU0+UZI=; b=RkMurpklxHNlDMYRRay3ZH7q8I+0Bj3G6tiKukB7J1so4K6kOW35OnsoaPTOVkm4NMl1dm oze1fABmSYlX2rFS9Gg/mUBjUL7Zs+pcApCZzqStrJGXuGof/29nnU0AKWXgIxrWHNda+a 9eNJMKBp7t+5L/m62H8zKwvWRFHvO0k= Received: from mail-ot1-f71.google.com (mail-ot1-f71.google.com [209.85.210.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-554-zHMvhxfAMqumSveiz8pmEA-1; Tue, 02 Nov 2021 07:17:18 -0400 X-MC-Unique: zHMvhxfAMqumSveiz8pmEA-1 Received: by mail-ot1-f71.google.com with SMTP id f5-20020a056830056500b00553e1fde941so9110228otc.5 for ; Tue, 02 Nov 2021 04:17:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=XXCD/y+EIIpD27UrY6lZoLmfoZFyT8+831AZbU0+UZI=; b=UoeI44SuIF938Hg/gjCYcLD7piFZOsqK5FE6EDWk28xyH2p+jMJZnwc5K6APFcgzBw cr6tRGIyYzDzakec1MpQWGWEW07xClSSAp6g9MAmpd6jlsvqwyMvFtLWPOp3K+aymMUf owd88JdkQ1Pyu43qVvGj8IhNVkwLB5bLcB8iTFPjCkZp5zBXgi6yfJYmxhC7u6/RYkKI ftqakN1Ytj2ETdGLWwoQNC4js7amHeIqdYrV4/PRaOIWZIOubuRjXmDuc911EaqxKyj5 PVo7Cr5M73HCxRxlfzk2cwZqQ/0eWpiel4M2eWYvptpc11u6MEo0i5x/5GLqBDX1XKbb TubA== X-Gm-Message-State: AOAM5333lcQaixdiBIbRkFNwRoDuhtiOb1yCqhegtgUeDVJkcJPh/KL5 R7sciItAQgytRoorOw0K7VRHB3UFv9lyrNR4d9GKLIWt5pyoSC84v3nDgm7uaGh1+CVnKOxZqNT UKUN8Ww3w10EJRI1rU97eWE0ZcJuP44g= X-Received: by 2002:a05:6808:1827:: with SMTP id bh39mr4471576oib.142.1635851838235; Tue, 02 Nov 2021 04:17:18 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyFTdbcjIKNzMUMViWnusXpyfZ4iD5Jq/omP/wQrIjWJS6KfUBAgrpQmxrQjrnodp/Cg761vzAhjiGQ5WHFbYs= X-Received: by 2002:a05:6808:1827:: with SMTP id bh39mr4471555oib.142.1635851838008; Tue, 02 Nov 2021 04:17:18 -0700 (PDT) MIME-Version: 1.0 References: <20210803205043.165034-1-mst@redhat.com> <20210803205043.165034-2-mst@redhat.com> <20210927053932-mutt-send-email-mst@kernel.org> In-Reply-To: From: Julia Suvorova Date: Tue, 2 Nov 2021 12:17:06 +0100 Message-ID: Subject: Re: [PULL 1/5] hw/pcie-root-port: Fix hotplug for PCI devices requiring IO To: =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsuvorov@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.133.124; envelope-from=jsuvorov@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) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.702, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marcel Apfelbaum , Peter Maydell , Igor Mammedov , QEMU Developers , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Nov 2, 2021 at 10:26 AM Daniel P. Berrang=C3=A9 wrote: > > On Mon, Sep 27, 2021 at 05:49:15AM -0400, Michael S. Tsirkin wrote: > > On Mon, Sep 27, 2021 at 10:33:42AM +0100, Daniel P. Berrang=C3=A9 wrote= : > > > On Tue, Aug 03, 2021 at 04:52:03PM -0400, Michael S. Tsirkin wrote: > > > > From: Marcel Apfelbaum > > > > > > > > Q35 has now ACPI hotplug enabled by default for PCI(e) devices. > > > > As opposed to native PCIe hotplug, guests like Fedora 34 > > > > will not assign IO range to pcie-root-ports not supporting > > > > native hotplug, resulting into a regression. > > > > > > > > Reproduce by: > > > > qemu-bin -M q35 -device pcie-root-port,id=3Dp1 -monitor stdio > > > > device_add e1000,bus=3Dp1 > > > > In the Guest OS the respective pcie-root-port will have the IO rang= e > > > > disabled. > > > > > > > > Fix it by setting the "reserve-io" hint capability of the > > > > pcie-root-ports so the firmware will allocate the IO range instead. > > > > > > > > Acked-by: Igor Mammedov > > > > Signed-off-by: Marcel Apfelbaum > > > > Message-Id: <20210802090057.1709775-1-marcel@redhat.com> > > > > Reviewed-by: Michael S. Tsirkin > > > > Signed-off-by: Michael S. Tsirkin > > > > --- > > > > hw/pci-bridge/gen_pcie_root_port.c | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > This change, when combined with the switch to ACPI based hotplug by > > > default, is responsible for a significant regression in QEMU 6.1.0 > > > > > > It is no longer possible to have more than 15 pcie-root-port devices > > > added to a q35 VM in 6.1.0. Before this I've had as many as 80+ devi= ces > > > present before I stopped trying to add more. > > > > > > https://gitlab.com/qemu-project/qemu/-/issues/641 > > > > > > This regression is significant, because it has broken the out of the > > > box default configuration that OpenStack uses for booting all VMs. > > > They add 16 pcie-root-ports by defalt to allow empty slots for device > > > hotplug under q35 [1]. > > > > > > Indeed, oops. Thanks for the report! > > We're at soft freeze now and this is still broken in git master. > I don't recall seeing a fix for this problem on list and no one has > commented on the bug report. > > Is anyone actively working on a fix for this release ? Yes, I'm working on a fix, going to send it soon. Best regards, Julia Suvorova. > If not, I'm going to post a patch to revert to PCI native > hotplug, because this was a significant regression in 6.1 that > breaks openstack out of the box and we can't leave it broken > again for 6.2. > > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberran= ge :| > |: https://libvirt.org -o- https://fstop138.berrange.c= om :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberran= ge :| > >