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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DC959C7EE24 for ; Tue, 30 May 2023 17:12:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231193AbjE3RMu (ORCPT ); Tue, 30 May 2023 13:12:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229673AbjE3RMs (ORCPT ); Tue, 30 May 2023 13:12:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0121CEA; Tue, 30 May 2023 10:12:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 83F8E61A4E; Tue, 30 May 2023 17:12:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7CF91C433D2; Tue, 30 May 2023 17:12:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685466766; bh=oMDauuBphE6JUcQ+uIrJvX7TM2de128E6fd+crN090A=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=bMNUevF8N4FowswMCFCB2xmyLAJMN7oa1AM+Z9xuaCrabO5PZThXqULzQiKg7insW YWV11lnmkWgOTUqczvVFVBYUoR+O+92fLauUU6GOttBn8oqXG+sSqQs9rj9hpaH0zj t7UN6bqshf0tdp8JnPsPhKZlj/WAlIPfKngglGgloBvxB3XjC5LR1KWtGd/JfNSWNr S0VzJUdoRyYgzhFlOK2mJ5m9w1iNbb2B3BYCNlI93zBLueqPBUbBddVL63ksAgIOzm zcaKtXF02lBCtn6ySqJHH/pvbIl08uoPA6Zeh6epk4t2E4oOMMrjlkU4DHJCM2e6i4 K6t6OVHg3wNAA== Date: Tue, 30 May 2023 12:12:44 -0500 From: Bjorn Helgaas To: Igor Mammedov Cc: linux-kernel@vger.kernel.org, mst@redhat.com, rafael@kernel.org, lenb@kernel.org, bhelgaas@google.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, mika.westerberg@linux.intel.com Subject: Re: [PATCH v2] PCI: acpiphp: Reassign resources on bridge if necessary Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230424191557.2464760-1-imammedo@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Apr 24, 2023 at 09:15:57PM +0200, Igor Mammedov wrote: > When using ACPI PCI hotplug, hotplugging a device with > large BARs may fail if bridge windows programmed by > firmware are not large enough. > > Reproducer: > $ qemu-kvm -monitor stdio -M q35 -m 4G \ > -global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=on \ > -device id=rp1,pcie-root-port,bus=pcie.0,chassis=4 \ > disk_image > > wait till linux guest boots, then hotplug device > (qemu) device_add qxl,bus=rp1 > > hotplug on guest side fails with: > pci 0000:01:00.0: [1b36:0100] type 00 class 0x038000 > pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x03ffffff] > pci 0000:01:00.0: reg 0x14: [mem 0x00000000-0x03ffffff] > pci 0000:01:00.0: reg 0x18: [mem 0x00000000-0x00001fff] > pci 0000:01:00.0: reg 0x1c: [io 0x0000-0x001f] > pci 0000:01:00.0: BAR 0: no space for [mem size 0x04000000] > pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x04000000] > pci 0000:01:00.0: BAR 1: no space for [mem size 0x04000000] > pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x04000000] > pci 0000:01:00.0: BAR 2: assigned [mem 0xfe800000-0xfe801fff] > pci 0000:01:00.0: BAR 3: assigned [io 0x1000-0x101f] > qxl 0000:01:00.0: enabling device (0000 -> 0003) Ugh, I just noticed that we turned on PCI_COMMAND_MEMORY even though BARs 0 and 1 haven't been assigned. How did that happen? It looks like pci_enable_resources() checks for that, but there must be a hole somewhere. > Unable to create vram_mapping > qxl: probe of 0000:01:00.0 failed with error -12