Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751448AbVKEK5u (ORCPT ); Sat, 5 Nov 2005 05:57:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751454AbVKEK5u (ORCPT ); Sat, 5 Nov 2005 05:57:50 -0500 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:59407 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S1751448AbVKEK5t (ORCPT ); Sat, 5 Nov 2005 05:57:49 -0500 Date: Sat, 5 Nov 2005 10:57:44 +0000 From: Russell King To: Linux Kernel List Subject: Re: [PATCH] [DRIVER MODEL] Fix depca Message-ID: <20051105105744.GA30315@flint.arm.linux.org.uk> Mail-Followup-To: Linux Kernel List References: <20051105105628.GE28438@flint.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20051105105628.GE28438@flint.arm.linux.org.uk> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2513 Lines: 81 Release code in driver modules is a potential cause of oopsen. The device may be in use by a userspace process, which will keep a reference to the device. If the module is unloaded, the module text will be freed. Subsequently, when the last reference is dropped, the release code will be called, which no longer exists. Use generic platform device allocation/release code in modules. Signed-off-by: Russell King diff --git a/drivers/net/depca.c b/drivers/net/depca.c --- a/drivers/net/depca.c +++ b/drivers/net/depca.c @@ -1470,15 +1470,6 @@ static int __init depca_mca_probe(struct ** ISA bus I/O device probe */ -static void depca_platform_release (struct device *device) -{ - struct platform_device *pldev; - - /* free device */ - pldev = to_platform_device (device); - kfree (pldev); -} - static void __init depca_platform_probe (void) { int i; @@ -1491,19 +1482,16 @@ static void __init depca_platform_probe * line, use it (if valid) */ if (io && io != depca_io_ports[i].iobase) continue; - - if (!(pldev = kmalloc (sizeof (*pldev), GFP_KERNEL))) + + pldev = platform_device_alloc(depca_string, i); + if (!pldev) continue; - memset (pldev, 0, sizeof (*pldev)); - pldev->name = depca_string; - pldev->id = i; pldev->dev.platform_data = (void *) depca_io_ports[i].iobase; - pldev->dev.release = depca_platform_release; depca_io_ports[i].device = pldev; - if (platform_device_register (pldev)) { - kfree (pldev); + if (platform_device_add(pldev)) { + platform_device_put(pldev); depca_io_ports[i].device = NULL; continue; } @@ -1515,6 +1503,7 @@ static void __init depca_platform_probe * allocated structure */ depca_io_ports[i].device = NULL; + pldev->dev.platform_data = NULL; platform_device_unregister (pldev); } } @@ -2112,6 +2101,7 @@ static void __exit depca_module_exit (vo for (i = 0; depca_io_ports[i].iobase; i++) { if (depca_io_ports[i].device) { + depca_io_ports[i].device->dev.platform_data = NULL; platform_device_unregister (depca_io_ports[i].device); depca_io_ports[i].device = NULL; } -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - 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/