From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032413AbXEHVyt (ORCPT ); Tue, 8 May 2007 17:54:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S967899AbXEHVyp (ORCPT ); Tue, 8 May 2007 17:54:45 -0400 Received: from mx1.redhat.com ([66.187.233.31]:39428 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967890AbXEHVyn (ORCPT ); Tue, 8 May 2007 17:54:43 -0400 Message-ID: <4640F1A0.6050700@redhat.com> Date: Tue, 08 May 2007 17:54:40 -0400 From: Chuck Ebbert Organization: Red Hat User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: kristen.c.accardi@intel.com CC: linux-kernel Subject: Re: kernel oops after ACPI dock initialization fails References: <4640EF28.2000903@redhat.com> In-Reply-To: <4640EF28.2000903@redhat.com> Content-Type: multipart/mixed; boundary="------------060500010902030402050902" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------060500010902030402050902 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Chuck Ebbert wrote: > In 2.6.21.1 when dock driver initialization fails it does a kfree() > of dock_station. (Below, this is due to some error installing a > notify handler.) Later when a bay is discovered it calls > is_dock_device() which attempts to lock the (nonexistent) > dock_station. Reason is this test in is_dock_device(): > > if (!dock_station) > return 0; > > dock_station is 0x6b6b6b6b after being freed. Either it needs > to be zeroed or some other flag should be used to decide > whether a dock station is present... > Untested patch attached. --------------060500010902030402050902 Content-Type: text/plain; name="acpi_fix_bay-dock_oops.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="acpi_fix_bay-dock_oops.patch" --- drivers/acpi/dock.c | 6 ++++++ 1 file changed, 6 insertions(+) --- 2.6.21-d390.orig/drivers/acpi/dock.c +++ 2.6.21-d390/drivers/acpi/dock.c @@ -698,6 +698,7 @@ static int dock_add(acpi_handle handle) if (ret) { printk(KERN_ERR PREFIX "Error %d registering dock device\n", ret); kfree(dock_station); + dock_station = NULL; return ret; } ret = device_create_file(&dock_device.dev, &dev_attr_docked); @@ -705,6 +706,7 @@ static int dock_add(acpi_handle handle) printk("Error %d adding sysfs file\n", ret); platform_device_unregister(&dock_device); kfree(dock_station); + dock_station = NULL; return ret; } ret = device_create_file(&dock_device.dev, &dev_attr_undock); @@ -713,6 +715,7 @@ static int dock_add(acpi_handle handle) device_remove_file(&dock_device.dev, &dev_attr_docked); platform_device_unregister(&dock_device); kfree(dock_station); + dock_station = NULL; return ret; } @@ -725,6 +728,7 @@ static int dock_add(acpi_handle handle) dd = alloc_dock_dependent_device(handle); if (!dd) { kfree(dock_station); + dock_station = NULL; ret = -ENOMEM; goto dock_add_err_unregister; } @@ -752,6 +756,7 @@ dock_add_err_unregister: device_remove_file(&dock_device.dev, &dev_attr_undock); platform_device_unregister(&dock_device); kfree(dock_station); + dock_station = NULL; return ret; } @@ -785,6 +790,7 @@ static int dock_remove(void) /* free dock station memory */ kfree(dock_station); + dock_station = NULL; return 0; } --------------060500010902030402050902--