Commit 93015236 authored May 06, 2011 by John Stultz

rtc: msm6242: Initialize drvdata before registering device



Commit f44f7f96 ("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 <w.sang@pengutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>

parent 03cf7c47

drivers/rtc/rtc-msm6242.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -214,6 +214,7 @@ static int __init msm6242_rtc_probe(struct platform_device *dev)
		error = -ENOMEM;
		goto out_free_priv;
		}
		platform_set_drvdata(dev, priv);

		rtc = rtc_device_register("rtc-msm6242", &dev->dev, &msm6242_rtc_ops,
		THIS_MODULE);
		@@ -223,10 +224,10 @@ static int __init msm6242_rtc_probe(struct platform_device *dev)
		}

		priv->rtc = rtc;
		platform_set_drvdata(dev, priv);
		return 0;

		out_unmap:
		platform_set_drvdata(dev, NULL);
		iounmap(priv->regs);
		out_free_priv:
		kfree(priv);