Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753403AbYJCXR4 (ORCPT ); Fri, 3 Oct 2008 19:17:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753882AbYJCXRk (ORCPT ); Fri, 3 Oct 2008 19:17:40 -0400 Received: from g4t0014.houston.hp.com ([15.201.24.17]:3187 "EHLO g4t0014.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754092AbYJCXRi (ORCPT ); Fri, 3 Oct 2008 19:17:38 -0400 From: Alex Chiang Subject: [PATCH v4 02/15] PCI Hotplug: serialize pci_hp_register/deregister To: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: jbarnes@virtuousgeek.org, kristen.c.accardi@intel.com, matthew@wil.cx, kaneshige.kenji@jp.fujitsu.com, Alex Chiang Date: Fri, 03 Oct 2008 17:17:37 -0600 Message-ID: <20081003231737.9989.94126.stgit@bob.kio> In-Reply-To: <20081003230125.9989.31145.stgit@bob.kio> References: <20081003230125.9989.31145.stgit@bob.kio> User-Agent: StGIT/0.14.3.215.gff3d MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2851 Lines: 92 Add explicit locking to pci_hp_register/deregister. For a given pci_slot, we want to make sure that the pci_slot->hotplug pointer isn't being changed from underneath us. Cc: jbarnes@virtuousgeek.org Cc: kristen.c.accardi@intel.com Cc: matthew@wil.cx Cc: kaneshige.kenji@jp.fujitsu.com Signed-off-by: Alex Chiang --- drivers/pci/hotplug/pci_hotplug_core.c | 7 +++++++ drivers/pci/slot.c | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c index 0e7a511..e00266b 100644 --- a/drivers/pci/hotplug/pci_hotplug_core.c +++ b/drivers/pci/hotplug/pci_hotplug_core.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #include @@ -554,6 +555,7 @@ out: * * Returns 0 if successful, anything else for an error. */ +static DEFINE_MUTEX(pci_hp_mutex); int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, const char *name) { @@ -583,7 +585,9 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, if (IS_ERR(pci_slot)) return PTR_ERR(pci_slot); + mutex_lock(&pci_hp_mutex); if (pci_slot->hotplug) { + mutex_unlock(&pci_hp_mutex); dbg("%s: already claimed\n", __func__); pci_destroy_slot(pci_slot); return -EBUSY; @@ -591,6 +595,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, slot->pci_slot = pci_slot; pci_slot->hotplug = slot; + mutex_unlock(&pci_hp_mutex); /* * Allow pcihp drivers to override the ACPI_PCI_SLOT name. @@ -635,6 +640,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) if (temp != hotplug) return -ENODEV; + mutex_lock(&pci_hp_mutex); spin_lock(&pci_hotplug_slot_list_lock); list_del(&hotplug->slot_list); spin_unlock(&pci_hotplug_slot_list_lock); @@ -645,6 +651,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) hotplug->release(hotplug); slot->hotplug = NULL; + mutex_unlock(&pci_hp_mutex); pci_destroy_slot(slot); return 0; diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c index 0c6db03..1fffb27 100644 --- a/drivers/pci/slot.c +++ b/drivers/pci/slot.c @@ -164,10 +164,10 @@ placeholder: pr_debug("%s: created pci_slot on %04x:%02x:%02x\n", __func__, pci_domain_nr(parent), parent->number, slot_nr); - out: +out: up_write(&pci_bus_sem); return slot; - err: +err: kfree(slot); slot = ERR_PTR(err); goto out; -- 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/