From: Wolfram Sang Date: Thu, 5 May 2011 09:46:15 +0000 (+0200) Subject: rtc: ep93xx: Initialize drvdata before registering device X-Git-Tag: v2.6.39~14^2~1^2~8 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=92d921c5def1a7b1411bc54859c0771b2cf2c08d rtc: ep93xx: 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: Alessandro Zummo CC: Thomas Gleixner CC: rtc-linux@googlegroups.com Signed-off-by: Wolfram Sang [Fixed up commit log -jstultz] Signed-off-by: John Stultz --- diff --git a/drivers/rtc/rtc-ep93xx.c b/drivers/rtc/rtc-ep93xx.c index 11ae64dcbf3c..335551d333b2 100644 --- a/drivers/rtc/rtc-ep93xx.c +++ b/drivers/rtc/rtc-ep93xx.c @@ -151,6 +151,7 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev) return -ENXIO; pdev->dev.platform_data = ep93xx_rtc; + platform_set_drvdata(pdev, rtc); rtc = rtc_device_register(pdev->name, &pdev->dev, &ep93xx_rtc_ops, THIS_MODULE); @@ -159,8 +160,6 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev) goto exit; } - platform_set_drvdata(pdev, rtc); - err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files); if (err) goto fail; @@ -168,9 +167,9 @@ static int __init ep93xx_rtc_probe(struct platform_device *pdev) return 0; fail: - platform_set_drvdata(pdev, NULL); rtc_device_unregister(rtc); exit: + platform_set_drvdata(pdev, NULL); pdev->dev.platform_data = NULL; return err; }