From mboxrd@z Thu Jan 1 00:00:00 1970 From: Taku Izumi Subject: [PATCH v3 6/8] ACPI, PCI: add acpi_pci_roots protection Date: Tue, 18 Sep 2012 15:24:40 +0900 Message-ID: <20120918152440.117dd1cb.izumi.taku@jp.fujitsu.com> References: <20120918151215.59ea763b.izumi.taku@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:53689 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755437Ab2IRGYd (ORCPT ); Tue, 18 Sep 2012 02:24:33 -0400 In-Reply-To: <20120918151215.59ea763b.izumi.taku@jp.fujitsu.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-pci@vger.kernel.org, bhelgaas@google.com Cc: linux-acpi@vger.kernel.org, kaneshige.kenji@jp.fujitsu.com, yinghai@kernel.org, jiang.liu@huawei.com Use mutex to protect acpi_pci_roots list against PCI host bridge hotplug operations. Signed-off-by: Taku Izumi --- drivers/acpi/pci_root.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) Index: Bjorn-next-0903/drivers/acpi/pci_root.c =================================================================== --- Bjorn-next-0903.orig/drivers/acpi/pci_root.c +++ Bjorn-next-0903/drivers/acpi/pci_root.c @@ -112,12 +112,17 @@ EXPORT_SYMBOL(acpi_pci_unregister_driver acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus) { struct acpi_pci_root *root; + struct acpi_handle *handle = NULL; + mutex_lock(&acpi_pci_root_lock); list_for_each_entry(root, &acpi_pci_roots, node) if ((root->segment == (u16) seg) && - (root->secondary.start == (u16) bus)) - return root->device->handle; - return NULL; + (root->secondary.start == (u16) bus)) { + handle = root->device->handle; + break; + } + mutex_unlock(&acpi_pci_root_lock); + return handle; } EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle); @@ -509,8 +514,9 @@ static int __devinit acpi_pci_root_add(s * TBD: Need PCI interface for enumeration/configuration of roots. */ - /* TBD: Locking */ + mutex_lock(&acpi_pci_root_lock); list_add_tail(&root->node, &acpi_pci_roots); + mutex_unlock(&acpi_pci_root_lock); printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n", acpi_device_name(device), acpi_device_bid(device), @@ -529,7 +535,7 @@ static int __devinit acpi_pci_root_add(s "Bus %04x:%02x not present in PCI namespace\n", root->segment, (unsigned int)root->secondary.start); result = -ENODEV; - goto end; + goto out_del_root; } /* @@ -539,7 +545,7 @@ static int __devinit acpi_pci_root_add(s */ result = acpi_pci_bind_root(device); if (result) - goto end; + goto out_del_root; /* * PCI Routing Table @@ -617,9 +623,11 @@ static int __devinit acpi_pci_root_add(s return 0; +out_del_root: + mutex_lock(&acpi_pci_root_lock); + list_del(&root->node); + mutex_unlock(&acpi_pci_root_lock); end: - if (!list_empty(&root->node)) - list_del(&root->node); kfree(root); return result; } @@ -649,11 +657,12 @@ static int acpi_pci_root_remove(struct a list_for_each_entry(driver, &acpi_pci_drivers, node) if (driver->remove) driver->remove(root); - mutex_unlock(&acpi_pci_root_lock); device_set_run_wake(root->bus->bridge, false); pci_acpi_remove_bus_pm_notifier(device); + list_del(&root->node); + mutex_unlock(&acpi_pci_root_lock); kfree(root); return 0; }