From patchwork Tue Oct 9 03:42:56 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 1567721 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id B7B3940135 for ; Tue, 9 Oct 2012 03:44:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754575Ab2JIDoO (ORCPT ); Mon, 8 Oct 2012 23:44:14 -0400 Received: from szxga01-in.huawei.com ([119.145.14.64]:31659 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754486Ab2JIDoI (ORCPT ); Mon, 8 Oct 2012 23:44:08 -0400 Received: from 172.24.2.119 (EHLO szxeml214-edg.china.huawei.com) ([172.24.2.119]) by szxrg01-dlp.huawei.com (MOS 4.3.4-GA FastPath queued) with ESMTP id AQF55131; Tue, 09 Oct 2012 11:44:03 +0800 (CST) Received: from SZXEML408-HUB.china.huawei.com (10.82.67.95) by szxeml214-edg.china.huawei.com (172.24.2.29) with Microsoft SMTP Server (TLS) id 14.1.323.3; Tue, 9 Oct 2012 11:43:10 +0800 Received: from [127.0.0.1] (10.108.108.229) by szxeml408-hub.china.huawei.com (10.82.67.95) with Microsoft SMTP Server id 14.1.323.3; Tue, 9 Oct 2012 11:42:58 +0800 Message-ID: <50739D40.8040005@huawei.com> Date: Tue, 9 Oct 2012 11:42:56 +0800 From: Jiang Liu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:9.0) Gecko/20111222 Thunderbird/9.0.1 MIME-Version: 1.0 To: Yijing Wang CC: Bjorn Helgaas , Hanjun Guo , , Yinghai Lu Subject: Re: [PATCH 0/7] disable bridge ari forwarding after connected ari device hot removed References: <1349751804-7476-1-git-send-email-wangyijing@huawei.com> In-Reply-To: <1349751804-7476-1-git-send-email-wangyijing@huawei.com> X-Originating-IP: [10.108.108.229] X-CFilter-Loop: Reflected Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org How about this patch, which disables ARI when adding new PCI devices? On 2012-10-9 11:03, Yijing Wang wrote: > pci_enable_ari will be called if an ARI pci device found, then set its bridge ARI Forwarding Enable > bit in Device Control 2 Register. But the bridge ARI Forwarding Enable bit will never be cleared > when an ARI device hot removed. > > my steps: > 1. Hot add an ARI pci device; > 2. Hot remove the ARI pci device; > 3. Hot add an non ARI pci device; > > In this case, after setp 3, we could only find fun 0 of non ARI pci device because of its bridge ARI Forwarding Enable > bit set. > > As PCIe Spec 2.0(6.13/441) recommends: > "Following a hot-plug event below a Downstream Port, it is strongly recommended that software > Clear the ARI Forwarding Enable bit in the Downstream Port until software determines that a > newly added component is in fact an ARI Device" > > This series of patches fix this problem. > > Yijing Wang (7): > PCI: rework pci_enable_ari for support disable ari forwarding > PCI, acpiphp: disable ARI forwarding for acpiphp > PCI, pciehp: disable ARI forwarding for pciehp > PCI, cpqphp: disable ARI forwarding for cpqphp > PCI, shpchp: disable ARI forwarding for shpchp > PCI, sgi: disable ARI forwarding for sgiphp > PCI, ibmphp: disable ARI forwarding for ibmphp > > drivers/pci/hotplug/acpiphp_glue.c | 1 + > drivers/pci/hotplug/cpci_hotplug_pci.c | 1 + > drivers/pci/hotplug/cpqphp_pci.c | 1 + > drivers/pci/hotplug/ibmphp_core.c | 1 + > drivers/pci/hotplug/pciehp_pci.c | 1 + > drivers/pci/hotplug/sgi_hotplug.c | 1 + > drivers/pci/hotplug/shpchp_pci.c | 1 + > drivers/pci/pci.c | 16 +++++++++++----- > drivers/pci/pci.h | 2 +- > drivers/pci/probe.c | 2 +- > 10 files changed, 20 insertions(+), 7 deletions(-) > > > > . > --- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 5485883..c841aa6 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2016,13 +2016,14 @@ void pci_free_cap_save_buffers(struct pci_dev *dev) void pci_enable_ari(struct pci_dev *dev) { u32 cap; + bool enable = true; struct pci_dev *bridge; if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn) return; if (!pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) - return; + enable = false; bridge = dev->bus->self; if (!bridge) @@ -2032,8 +2033,15 @@ void pci_enable_ari(struct pci_dev *dev) if (!(cap & PCI_EXP_DEVCAP2_ARI)) return; - pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_ARI); - bridge->ari_enabled = 1; + if (enable) { + pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_ARI); + bridge->ari_enabled = 1; + } else { + pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_ARI); + bridge->ari_enabled = 0; + } } /**