From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: "Rafael J. Wysocki" To: ACPI Devel Maling List Cc: LKML , Linux PCI , Bjorn Helgaas , Toshi Kani , Yinghai Lu Subject: [Update][PATCH 3/6] ACPI / hotplug: Fix handle_root_bridge_removal() Date: Mon, 04 Nov 2013 14:33:09 +0100 Message-ID: <6808835.gmCqHn1NaE@vostro.rjw.lan> In-Reply-To: <2970389.SeMGM45Qln@vostro.rjw.lan> References: <5839747.7HXXGHmMBd@vostro.rjw.lan> <2970389.SeMGM45Qln@vostro.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-acpi-owner@vger.kernel.org List-ID: From: Rafael J. Wysocki It is required to do get_device() on the struct acpi_device in question before passing it to acpi_bus_hot_remove_device() through acpi_os_hotplug_execute(), because acpi_bus_hot_remove_device() calls acpi_scan_hot_remove() that does put_device() on that object. The ACPI PCI root removal routine, handle_root_bridge_removal(), doesn't do that, which may lead to premature freeing of the device object or to executing put_device() on an object that has been freed already. Fix this problem by making handle_root_bridge_removal() use get_device() as appropriate. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/pci_root.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) Index: linux-pm/drivers/acpi/pci_root.c =================================================================== --- linux-pm.orig/drivers/acpi/pci_root.c +++ linux-pm/drivers/acpi/pci_root.c @@ -608,9 +608,12 @@ static void handle_root_bridge_removal(s ej_event->device = device; ej_event->event = ACPI_NOTIFY_EJECT_REQUEST; + get_device(&device->dev); status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event); - if (ACPI_FAILURE(status)) + if (ACPI_FAILURE(status)) { + put_device(&device->dev); kfree(ej_event); + } } static void _handle_hotplug_event_root(struct work_struct *work)