Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933440Ab0GAVrx (ORCPT ); Thu, 1 Jul 2010 17:47:53 -0400 Received: from kroah.org ([198.145.64.141]:32783 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759048Ab0GAVOI (ORCPT ); Thu, 1 Jul 2010 17:14:08 -0400 X-Mailbox-Line: From gregkh@clark.site Thu Jul 1 10:42:54 2010 Message-Id: <20100701174254.703438805@clark.site> User-Agent: quilt/0.48-10.1 Date: Thu, 01 Jul 2010 10:43:08 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Dan Carpenter , Alessandro Zummo , Paul Gortmaker , Malte Schroder , Ralf Baechle , Herton Ronaldo Krzesinski Subject: [098/200] rtc-cmos: do dev_set_drvdata() earlier in the initialization In-Reply-To: <20100701175201.GA2149@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2087 Lines: 64 2.6.34-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 6ba8bcd457d9fc793ac9435aa2e4138f571d4ec5 upstream. The bug is an oops when dev_get_drvdata() returned null in cmos_update_irq_enable(). The call tree looks like this: rtc_dev_ioctl() => rtc_update_irq_enable() => cmos_update_irq_enable() It's caused by a race condition in the module initialization. It is rtc_device_register() which makes the ioctl operations live so I moved the call to dev_set_drvdata() before the call to rtc_device_register(). Addresses https://bugzilla.kernel.org/show_bug.cgi?id=15963 Reported-by: Randy Dunlap Signed-off-by: Dan Carpenter Tested-by: Randy Dunlap Cc: Alessandro Zummo Cc: Paul Gortmaker Cc: Malte Schroder Cc: Ralf Baechle Cc: Herton Ronaldo Krzesinski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/rtc/rtc-cmos.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -719,6 +719,9 @@ cmos_do_probe(struct device *dev, struct } } + cmos_rtc.dev = dev; + dev_set_drvdata(dev, &cmos_rtc); + cmos_rtc.rtc = rtc_device_register(driver_name, dev, &cmos_rtc_ops, THIS_MODULE); if (IS_ERR(cmos_rtc.rtc)) { @@ -726,8 +729,6 @@ cmos_do_probe(struct device *dev, struct goto cleanup0; } - cmos_rtc.dev = dev; - dev_set_drvdata(dev, &cmos_rtc); rename_region(ports, dev_name(&cmos_rtc.rtc->dev)); spin_lock_irq(&rtc_lock); -- 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/