From patchwork Thu Oct 22 23:07:11 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 534636 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 13EB6141321 for ; Fri, 23 Oct 2015 10:07:41 +1100 (AEDT) Received: from localhost ([::1]:34960 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZpOxP-00028J-3E for incoming@patchwork.ozlabs.org; Thu, 22 Oct 2015 19:07:39 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42100) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZpOx5-0001rZ-CE for qemu-devel@nongnu.org; Thu, 22 Oct 2015 19:07:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZpOx0-000188-9d for qemu-devel@nongnu.org; Thu, 22 Oct 2015 19:07:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51390) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZpOx0-00017M-4S for qemu-devel@nongnu.org; Thu, 22 Oct 2015 19:07:14 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id EB03BC0B2E12 for ; Thu, 22 Oct 2015 23:07:12 +0000 (UTC) Received: from gimli.home (ovpn-113-42.phx2.redhat.com [10.3.113.42]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t9MN7BeR002242; Thu, 22 Oct 2015 19:07:11 -0400 From: Alex Williamson To: qemu-devel@nongnu.org Date: Thu, 22 Oct 2015 17:07:11 -0600 Message-ID: <20151022230649.31426.69330.stgit@gimli.home> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: marcel@redhat.com, mst@redhat.com Subject: [Qemu-devel] [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 3e26f92..b6846ee 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 "trace.h" @@ -48,9 +49,29 @@ 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); trace_pci_cfg_write(pci_dev->name, PCI_SLOT(pci_dev->devfn), PCI_FUNC(pci_dev->devfn), addr, val); @@ -62,6 +83,11 @@ 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); ret = pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr)); trace_pci_cfg_read(pci_dev->name, PCI_SLOT(pci_dev->devfn),