From patchwork Tue Nov 10 20:26:04 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 542605 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BDD83141458 for ; Wed, 11 Nov 2015 07:26:28 +1100 (AEDT) Received: from localhost ([::1]:35404 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZwFUo-00017A-Hl for incoming@patchwork.ozlabs.org; Tue, 10 Nov 2015 15:26:26 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52965) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZwFUY-0000pO-Sk for qemu-devel@nongnu.org; Tue, 10 Nov 2015 15:26:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZwFUT-00072N-TZ for qemu-devel@nongnu.org; Tue, 10 Nov 2015 15:26:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33508) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZwFUT-00072D-KY for qemu-devel@nongnu.org; Tue, 10 Nov 2015 15:26:05 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 3ED10C0AF3DA for ; Tue, 10 Nov 2015 20:26:05 +0000 (UTC) Received: from gimli.home (ovpn-113-92.phx2.redhat.com [10.3.113.92]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tAAKQ449007235; Tue, 10 Nov 2015 15:26:04 -0500 From: Alex Williamson To: qemu-devel@nongnu.org Date: Tue, 10 Nov 2015 13:26:04 -0700 Message-ID: <20151110202504.7436.48991.stgit@gimli.home> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: alex.williamson@redhat.com, mst@redhat.com Subject: [Qemu-devel] [RESEND PATCH] pci: Adjust PCI config limit based on bus topology X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org A conventional PCI bus does not support config space accesses above the standard 256 byte configuration space. PCIe-to-PCI bridges are not permitted to forward transactions if the extended register address field is non-zero and must handle it as an unsupported request (PCIe bridge spec rev 1.0, 4.1.3, 4.1.4). Therefore, we should not support extended config space if there is a conventional bus anywhere on the path to a device. Signed-off-by: Alex Williamson --- hw/pci/pci_host.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/hw/pci/pci_host.c b/hw/pci/pci_host.c index 49f59a5..3a3e294 100644 --- a/hw/pci/pci_host.c +++ b/hw/pci/pci_host.c @@ -19,6 +19,7 @@ */ #include "hw/pci/pci.h" +#include "hw/pci/pci_bridge.h" #include "hw/pci/pci_host.h" #include "hw/pci/pci_bus.h" #include "trace.h" @@ -49,9 +50,29 @@ static inline PCIDevice *pci_dev_find_by_addr(PCIBus *bus, uint32_t addr) return pci_find_device(bus, bus_num, devfn); } +static void pci_adjust_config_limit(PCIBus *bus, uint32_t *limit) +{ + if (*limit > PCI_CONFIG_SPACE_SIZE) { + if (!pci_bus_is_express(bus)) { + *limit = PCI_CONFIG_SPACE_SIZE; + return; + } + + if (!pci_bus_is_root(bus)) { + PCIDevice *bridge = pci_bridge_get_device(bus); + pci_adjust_config_limit(bridge->bus, limit); + } + } +} + void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr, uint32_t limit, uint32_t val, uint32_t len) { + pci_adjust_config_limit(pci_dev->bus, &limit); + if (limit <= addr) { + return; + } + assert(len <= 4); /* non-zero functions are only exposed when function 0 is present, * allowing direct removal of unexposed functions. @@ -70,6 +91,11 @@ uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr, { uint32_t ret; + pci_adjust_config_limit(pci_dev->bus, &limit); + if (limit <= addr) { + return ~0x0; + } + assert(len <= 4); /* non-zero functions are only exposed when function 0 is present, * allowing direct removal of unexposed functions.