Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755130Ab2BEHAi (ORCPT ); Sun, 5 Feb 2012 02:00:38 -0500 Received: from acsinet15.oracle.com ([141.146.126.227]:24812 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755043Ab2BEHAe (ORCPT ); Sun, 5 Feb 2012 02:00:34 -0500 From: Yinghai Lu To: Jesse Barnes , Benjamin Herrenschmidt , Tony Luck Cc: Bjorn Helgaas , Dominik Brodowski , Andrew Morton , Linus Torvalds , Greg Kroah-Hartman , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Yinghai Lu Subject: [PATCH 18/24] PCI: Double checking setting for bus register and bus struct. Date: Sat, 4 Feb 2012 22:58:02 -0800 Message-Id: <1328425088-6562-19-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1328425088-6562-1-git-send-email-yinghai@kernel.org> References: <1328425088-6562-1-git-send-email-yinghai@kernel.org> X-Source-IP: acsinet21.oracle.com [141.146.126.237] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090204.4F2E290A.001B,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2738 Lines: 73 User could use setpci change bridge's bus register. that could make value of register and struct is out of sync. User later will use rescan to see the devices is moving. In the rescaning, we need to double check the range and remove the old struct at first. to make thing working user may need have script to remove children devices under bridge at first, and then use setpci update bus register and then rescan. Signed-off-by: Yinghai Lu --- drivers/pci/probe.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 files changed, 40 insertions(+), 0 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 2117364..b0c2aa1 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -815,6 +815,46 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, (primary != bus->number || secondary <= bus->number)) broken = 1; + if (!pass && dev->subordinate) { + child = dev->subordinate; + /* + * User could change bus register in bridge manually with + * setpci and rescan. So double check the setting, and remove + * old structs. Don't set broken yet, let following check + * to see if the new setting good. + */ + if (primary != child->primary || + secondary != child->secondary || + subordinate != child->subordinate) { + dev_info(&dev->dev, + "someone changed bus register from pri:%02x, sec:%02x, sub:%02x to pri:%02x, sec:%02x, sub:%02x\n", + child->primary, child->secondary, child->subordinate, + primary, secondary, subordinate); + if (!list_empty(&dev->subordinate->devices)) { + u32 old_buses; + + dev_info(&dev->dev, + "but children devices are not removed manually before that.\n"); + /* + * Try best to remove left children devices + * but we need to set bus register back, otherwise + * We can not access children device and stop them + */ + old_buses = (buses & 0xff000000) + | ((unsigned int)(child->primary) << 0) + | ((unsigned int)(child->secondary) << 8) + | ((unsigned int)(child->subordinate) << 16); + pci_write_config_dword(dev, PCI_PRIMARY_BUS, + old_buses); + pci_remove_behind_bridge(dev); + pci_write_config_dword(dev, PCI_PRIMARY_BUS, + buses); + } + pci_remove_bus(dev->subordinate); + dev->subordinate = NULL; + } + } + /* more strict checking */ if (!pass && !broken && !dev->subordinate) broken = pci_bridge_check_busn_broken(bus, dev, -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/