[PATCH 09/13] SOUND: fix race in device_create

From: Greg Kroah-Hartman
Date: Tue May 20 2008 - 18:40:56 EST


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@xxxxxxxx>
Cc: Jaroslav Kysela <perex@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
sound/core/sound.c | 8 +++-----
1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/sound/core/sound.c b/sound/core/sound.c
index 812f91b..6c8ab48 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -259,8 +259,9 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
return minor;
}
snd_minors[minor] = preg;
- preg->dev = device_create(sound_class, device, MKDEV(major, minor),
- "%s", name);
+ preg->dev = device_create_drvdata(sound_class, device,
+ MKDEV(major, minor),
+ private_data, "%s", name);
if (IS_ERR(preg->dev)) {
snd_minors[minor] = NULL;
mutex_unlock(&sound_mutex);
@@ -269,9 +270,6 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
return minor;
}

- if (preg->dev)
- dev_set_drvdata(preg->dev, private_data);
-
mutex_unlock(&sound_mutex);
return 0;
}
--
1.5.5.1

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