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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 7A551C4338F for ; Tue, 27 Jul 2021 09:03:45 +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 1916761252 for ; Tue, 27 Jul 2021 09:03:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1916761252 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]:47752 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m8J04-0000KQ-7c for qemu-devel@archiver.kernel.org; Tue, 27 Jul 2021 05:03:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55694) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m8Iz0-0007Ku-Vn for qemu-devel@nongnu.org; Tue, 27 Jul 2021 05:02:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:30901) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m8Iyz-0007p6-9p for qemu-devel@nongnu.org; Tue, 27 Jul 2021 05:02:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627376556; 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=fLKr309ut0KG6rKV+Ejhlj89Kw2sHa3TLR3vopNSEko=; b=WwVENJvbcxT28mUd7VXS57qUgATN9CWtFR1ew87cQlTF+K+wQujb92KuU5VSX/GQnN84BW PQvga7KkB0S97DQJ7GFgD9TDdoxVVjSk0PkjgHULUmVc5BwaiQTzYde+RcW24PUQOP0VDT PcE3pEmcA1BgQs9yRJHulIcj50kVS6w= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-55-1P0BnJvjNZCJYAXlWYgljQ-1; Tue, 27 Jul 2021 05:02:35 -0400 X-MC-Unique: 1P0BnJvjNZCJYAXlWYgljQ-1 Received: by mail-ed1-f70.google.com with SMTP id y19-20020a0564021713b02903bbfec89ebcso1343960edu.16 for ; Tue, 27 Jul 2021 02:02:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=fLKr309ut0KG6rKV+Ejhlj89Kw2sHa3TLR3vopNSEko=; b=h8ZwuIkjpJMTo/x9mHep9TqcDmQo8fCb1Cvf50kQMrIafd6ZWiaeEipsa4VlO/iTpy zCwRaFf5LMQDd0vShDgr1341PBPUyTgr1xYdeuGQtbrCOWcQk6TvsZ8BLJeEGF+6NWz3 /P2mjCNVyXTo5bttcrPKzM1V9XgycXgZo9t25qvDljYhwlIoGhnfco4Exnzf68k8qgbU S3DNMSH+EV+lH8VntT9Bi+5V4qEUklL2uq78FKFtexJTwjiqZdolHE8TOmFIvQMXB45k eyNx4XTN6ZIZD6J5W36DhD8TqlOu6t+uVWvv5vni0GLvapJEZskWlyOOD6H5uRCxGyN7 cu4w== X-Gm-Message-State: AOAM533o/kCYEFlxmR4JImmN4/lB4GoPUcBMKM23dPTRH81xeXbFUSkz MJbh+3aNo17LybcGZK8N7EF1yrq/Kiucq6WvEOoo4ggAGRPjrwfoAJwQZi1OfJLnemFH02HaC/8 Lt3HZ3duQOEOyw4U= X-Received: by 2002:a17:906:580c:: with SMTP id m12mr18822025ejq.32.1627376553841; Tue, 27 Jul 2021 02:02:33 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwU5PCrx0hfrfwRndVexTbirwLIr2TfYO3mXdGz0M4KNLOnCVTn6PI7NilylPuB5NSstLCH9w== X-Received: by 2002:a17:906:580c:: with SMTP id m12mr18822016ejq.32.1627376553715; Tue, 27 Jul 2021 02:02:33 -0700 (PDT) Received: from redhat.com ([2.55.128.141]) by smtp.gmail.com with ESMTPSA id y6sm963755edv.88.2021.07.27.02.02.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Jul 2021 02:02:33 -0700 (PDT) Date: Tue, 27 Jul 2021 05:02:29 -0400 From: "Michael S. Tsirkin" To: Ard Biesheuvel Subject: Re: aarch64 efi boot failures with qemu 6.0+ Message-ID: <20210727050159-mutt-send-email-mst@kernel.org> References: <20210724185234.GA2265457@roeck-us.net> <20210725181334-mutt-send-email-mst@kernel.org> <14aff6ab-0b96-fe22-bc35-18d2e8528a5b@roeck-us.net> <2a4076fd-2225-b3a8-7a1e-3bc090046673@redhat.com> <20210727004401-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=mst@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=-0.717, 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_H4=0.001, RCVD_IN_MSPIKE_WL=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: , Cc: Jiahui Cen , Ard Biesheuvel , qemu-devel@nongnu.org, Bjorn Helgaas , Igor Mammedov , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= , Guenter Roeck Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Jul 27, 2021 at 09:04:20AM +0200, Ard Biesheuvel wrote: > On Tue, 27 Jul 2021 at 07:12, Guenter Roeck wrote: > > > > On 7/26/21 9:45 PM, Michael S. Tsirkin wrote: > > > On Mon, Jul 26, 2021 at 06:00:57PM +0200, Ard Biesheuvel wrote: > > >> (cc Bjorn) > > >> > > >> On Mon, 26 Jul 2021 at 11:08, Philippe Mathieu-Daudé wrote: > > >>> > > >>> On 7/26/21 12:56 AM, Guenter Roeck wrote: > > >>>> On 7/25/21 3:14 PM, Michael S. Tsirkin wrote: > > >>>>> On Sat, Jul 24, 2021 at 11:52:34AM -0700, Guenter Roeck wrote: > > >>>>>> Hi all, > > >>>>>> > > >>>>>> starting with qemu v6.0, some of my aarch64 efi boot tests no longer > > >>>>>> work. Analysis shows that PCI devices with IO ports do not instantiate > > >>>>>> in qemu v6.0 (or v6.1-rc0) when booting through efi. The problem affects > > >>>>>> (at least) ne2k_pci, tulip, dc390, and am53c974. The problem only > > >>>>>> affects > > >>>>>> aarch64, not x86/x86_64. > > >>>>>> > > >>>>>> I bisected the problem to commit 0cf8882fd0 ("acpi/gpex: Inform os to > > >>>>>> keep firmware resource map"). Since this commit, PCI device BAR > > >>>>>> allocation has changed. Taking tulip as example, the kernel reports > > >>>>>> the following PCI bar assignments when running qemu v5.2. > > >>>>>> > > >>>>>> [ 3.921801] pci 0000:00:01.0: [1011:0019] type 00 class 0x020000 > > >>>>>> [ 3.922207] pci 0000:00:01.0: reg 0x10: [io 0x0000-0x007f] > > >>>>>> [ 3.922505] pci 0000:00:01.0: reg 0x14: [mem 0x10000000-0x1000007f] > > >> > > >> IIUC, these lines are read back from the BARs > > >> > > >>>>>> [ 3.927111] pci 0000:00:01.0: BAR 0: assigned [io 0x1000-0x107f] > > >>>>>> [ 3.927455] pci 0000:00:01.0: BAR 1: assigned [mem > > >>>>>> 0x10000000-0x1000007f] > > >>>>>> > > >> > > >> ... and this is the assignment created by the kernel. > > >> > > >>>>>> With qemu v6.0, the assignment is reported as follows. > > >>>>>> > > >>>>>> [ 3.922887] pci 0000:00:01.0: [1011:0019] type 00 class 0x020000 > > >>>>>> [ 3.923278] pci 0000:00:01.0: reg 0x10: [io 0x0000-0x007f] > > >>>>>> [ 3.923451] pci 0000:00:01.0: reg 0x14: [mem 0x10000000-0x1000007f] > > >>>>>> > > >> > > >> The problem here is that Linux, for legacy reasons, does not support > > >> I/O ports <= 0x1000 on PCI, so the I/O assignment created by EFI is > > >> rejected. > > >> > > >> This might make sense on x86, where legacy I/O ports may exist, but on > > >> other architectures, this makes no sense. > > > > > > > > > Fixing Linux makes sense but OTOH EFI probably shouldn't create mappings > > > that trip up existing guests, right? > > > > > > > I think it is difficult to draw a line. Sure, maybe EFI should not create > > such mappings, but then maybe qemu should not suddenly start to enforce > > those mappings for existing guests either. > > > > EFI creates the mappings primarily for itself, and up until DSM #5 > started to be enforced, all PCI resource allocations that existed at > boot were ignored by Linux and recreated from scratch. > > Also, the commit in question looks dubious to me. I don't think it is > likely that Linux would fail to create a resource tree. What does > happen is that BARs get moved around, which may cause trouble in some > cases: for instance, we had to add special code to the EFI framebuffer > driver to copy with framebuffer BARs being relocated. > > > For my own testing, I simply reverted commit 0cf8882fd0 in my copy of > > qemu. That solves my immediate problem, giving us time to find a solution > > that is acceptable for everyone. After all, it doesn't look like anyone > > else has noticed the problem, so there is no real urgency. > > > > I would argue that it is better to revert that commit. DSM #5 has a > long history of debate and misinterpretation, and while I think we > ended up with something sane, I don't think we should be using it in > this particular case. Re-reading it I have to agree. I think I misunderstood the spec and guest behaviour when I applied it. -- MST