if (file->private_data) { kfree(file->private_data); file->private_data = NULL; }  
kfree(file->private_data); file->private_data = NULL; 
static int usb_device_release(struct inode *inode, struct file *file){	if (file->private_data) {		kfree(file->private_data);		file->private_data = NULL;	}        return 0;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/1bc3c9e1e44c2059fe2ffa6ff70ad0a925d7b05f/devices.c/clean/drivers/usb/core/devices.c