fbdev: fix race in device_create

There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Greg Kroah-Hartman 2008-05-15 13:44:08 -07:00
parent 19051c5035
commit 8b485877e0

View file

@ -26,6 +26,7 @@
#include <linux/ctype.h>
#include <linux/idr.h>
#include <linux/err.h>
#include <linux/kdev_t.h>
static ssize_t display_show_name(struct device *dev,
struct device_attribute *attr, char *buf)
@ -152,10 +153,13 @@ struct display_device *display_device_register(struct display_driver *driver,
mutex_unlock(&allocated_dsp_lock);
if (!ret) {
new_dev->dev = device_create(display_class, parent, 0,
"display%d", new_dev->idx);
new_dev->dev = device_create_drvdata(display_class,
parent,
MKDEV(0,0),
new_dev,
"display%d",
new_dev->idx);
if (!IS_ERR(new_dev->dev)) {
dev_set_drvdata(new_dev->dev, new_dev);
new_dev->parent = parent;
new_dev->driver = driver;
mutex_init(&new_dev->lock);