From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754613Ab1EGBVt (ORCPT ); Fri, 6 May 2011 21:21:49 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:44133 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754223Ab1EGBVK (ORCPT ); Fri, 6 May 2011 21:21:10 -0400 From: John Stultz To: lkml Cc: John Stultz , Wolfram Sang , Alessandro Zummo , Thomas Gleixner , rtc-linux@googlegroups.com Subject: [PATCH 10/11] rtc: rp5c01: Initialize drvdata before registering device Date: Fri, 6 May 2011 18:20:53 -0700 Message-Id: <1304731254-3238-11-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 1.7.3.2.146.gca209 In-Reply-To: <1304731254-3238-1-git-send-email-john.stultz@linaro.org> References: <1304731254-3238-1-git-send-email-john.stultz@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the device or platform drvdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the drvdata is initialized prior to registering the rtc device. CC: Wolfram Sang CC: Alessandro Zummo CC: Thomas Gleixner CC: rtc-linux@googlegroups.com Signed-off-by: John Stultz --- drivers/rtc/rtc-rp5c01.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-rp5c01.c b/drivers/rtc/rtc-rp5c01.c index 694da39..359da6d 100644 --- a/drivers/rtc/rtc-rp5c01.c +++ b/drivers/rtc/rtc-rp5c01.c @@ -249,15 +249,15 @@ static int __init rp5c01_rtc_probe(struct platform_device *dev) spin_lock_init(&priv->lock); + platform_set_drvdata(dev, priv); + rtc = rtc_device_register("rtc-rp5c01", &dev->dev, &rp5c01_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { error = PTR_ERR(rtc); goto out_unmap; } - priv->rtc = rtc; - platform_set_drvdata(dev, priv); error = sysfs_create_bin_file(&dev->dev.kobj, &priv->nvram_attr); if (error) @@ -268,6 +268,7 @@ static int __init rp5c01_rtc_probe(struct platform_device *dev) out_unregister: rtc_device_unregister(rtc); out_unmap: + platform_set_drvdata(dev, NULL); iounmap(priv->regs); out_free_priv: kfree(priv); -- 1.7.3.2.146.gca209