From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752022AbZEYGyB (ORCPT ); Mon, 25 May 2009 02:54:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751619AbZEYGxy (ORCPT ); Mon, 25 May 2009 02:53:54 -0400 Received: from ozlabs.org ([203.10.76.45]:47617 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751242AbZEYGxx (ORCPT ); Mon, 25 May 2009 02:53:53 -0400 To: Andrew Morton CC: , Greg Kroah-Hartman From: Benjamin Herrenschmidt Date: Mon, 25 May 2009 16:53:31 +1000 Subject: [PATCH] devres: WARN() and return, don't crash on device_del() of uninitialized device Message-Id: <20090525065346.1D991DE2AC@ozlabs.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I just debugged an obscure crash caused by a device_del() of a all NULL'd out struct device (in usb-serial) and found that a patch like this one would have saved me time (in addition to improved chances of a bug report from users hitting similar driver bugs). Signed-off-by: Benjamin Herrenschmidt --- drivers/base/devres.c | 5 +++++ 1 file changed, 5 insertions(+) --- linux-work.orig/drivers/base/devres.c 2009-05-25 16:43:46.000000000 +1000 +++ linux-work/drivers/base/devres.c 2009-05-25 16:46:36.000000000 +1000 @@ -428,6 +428,11 @@ int devres_release_all(struct device *de { unsigned long flags; + /* Looks like an uninitialized device structure */ + if (dev->devres_head.next == NULL) { + WARN(1); + return -ENODEV; + } spin_lock_irqsave(&dev->devres_lock, flags); return release_nodes(dev, dev->devres_head.next, &dev->devres_head, flags);