From: John Stultz Date: Sat, 7 May 2011 00:31:20 +0000 (-0700) Subject: rtc: rp5c01: Initialize drvdata before registering device X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=130107b270f9a8ef1b50e02140a381c44a6abd68;p=openwrt%2Fstaging%2Fblogic.git rtc: rp5c01: Initialize drvdata before registering device 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 --- diff --git a/drivers/rtc/rtc-rp5c01.c b/drivers/rtc/rtc-rp5c01.c index 694da39b6dd2..359da6d020b9 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);