V4l1: video_register_device(), Segmentation Fault.

This is code which fails when video_register_device is called. It does nothing 
particular. It just tries to call that function when the module is loaded into 
the memory.  I really don't know where is the error...
Below there are also the kernel message and the ksymoops output about it. The 
kernel version is 2.4.20 on an i686 processor. I also tried with 2.4.19.


/* BEGIN */

#define MODULE
#define __KERNEL__

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/videodev.h>

struct my_device {
	struct video_device v4ldev; /* V4L structure */
};

static int my_open(struct inode* inode, struct file* filp)
{
	return -1;
}

static int my_release(struct inode* inode, struct file* filp)
{
	return 0;
}

static ssize_t my_read(struct file* filp, char* buf,
                            size_t count, loff_t* f_pos)
{
	return 0;
}

static unsigned int my_poll(struct file* filp, poll_table* wait)
{
	return 0;
}

static int my_mmap(struct file* filp, struct vm_area_struct *vma)
{
	return -1;
}

static int my_ioctl(struct inode* inode, struct file* filp,
                         unsigned int cmd, unsigned long arg)
{
		return -1;
}

struct file_operations my_fops = {
	open:    my_open,
	release: my_release,
	read:    my_read,
	ioctl:   my_ioctl,
	poll:    my_poll,
	mmap:    my_mmap,
	owner:   THIS_MODULE
};

int my_probe()
{
	struct my_device* camera;
	int err = 0;

	printk(KERN_DEBUG "mydev: Probe called.\n");

	camera = (struct my_device*)
	         kmalloc(sizeof(struct my_device), GFP_KERNEL);

	if (!camera) {
		printk(KERN_WARNING "mydev: couldn't allocate memory\n");
		goto fail;
	}
	
	strcpy(camera->v4ldev.name,  "MYDEV");
	camera->v4ldev.type = VID_TYPE_CAPTURE;
	camera->v4ldev.hardware = 1000; /* whatever ? */
	camera->v4ldev.fops = &my_fops;
	camera->v4ldev.priv = NULL;
	camera->v4ldev.minor = -1;

	printk(KERN_DEBUG "mydev: Calling video_register_device..\n");

	err = video_register_device(&camera->v4ldev,VFL_TYPE_GRABBER, -1);

	if (err) {
		printk(KERN_ERR "mydev: v4l registration failed.\n");
		goto fail;
	}

	printk(KERN_DEBUG "mydev: V4L device registered\n");

	return 0;

fail:
	if (camera) kfree(camera);
	return -1;
}



static int __init my_module_init(void)
{
	return my_probe();
}

static void __exit my_module_cleanup(void)
{
}

module_init(my_module_init);
module_exit(my_module_cleanup);

/* END MODULE */


This is the kernel message:
 
mydev: Probe called.
mydev: Calling video_register_device..

Unable to handle kernel NULL pointer dereference at virtual address 000000b0
 printing eip:
000000b0
*pde = 00000000
Oops: 0000
CPU:    0
EIP:    0010:[<000000b0>]    Tainted: P
EFLAGS: 00010202
eax: 000000b0   ebx: 00000003   ecx: d0aed1e0   edx: d0aed260
esi: 00000000   edi: cf0e86a0   ebp: 0000000c   esp: c1cb7ed0
ds: 0018   es: 0018   ss: 0018
Process insmod (pid: 2425, stackpage=c1cb7000)
Stack: d0aecb0b cf0e86a0 d0aed080 c02f44ea 00000246 0000002a c1cb7f18 cf0e86a0
       00000001 00000001 c1cb7f18 d2453130 cf0e86a0 00000000 ffffffff c102c01c
       c02933e4 d2453000 c1cb7f28 d245318b 00000001 00000001 00000001 c0119015
Call Trace:    [<d0aecb0b>] [<d0aed080>] [<d2453130>] [<d245318b>] 
[<c0119015>]
  [<d245336c>] [<d2453060>] [<c0106dc3>]

Code:  Bad EIP value.


Ksymoops output:

ksymoops 2.4.3 on i686 2.4.20.  Options used
     -V (default)
     -k /proc/ksyms (default)
     -l /proc/modules (default)
     -o /lib/modules/2.4.20/ (default)
     -m /boot/System.map-2.4.20 (default)

>>EIP; 000000b0 Before first symbol   <=====
Trace; d0aecb0a <[videodev]video_register_device+13a/1d0>
Trace; d0aed080 <[videodev].text.end+392/4f2>
Trace; d2453130 <[w9968cf2]my_probe+70/c0>
Trace; d245318a <[w9968cf2]my_module_init+a/10>
Trace; c0119014 <sys_init_module+534/5f0>
Trace; d245336c <[w9968cf2].text.end+1ce/202>
Trace; d2453060 <[w9968cf2]my_open+0/10>
Trace; c0106dc2 <system_call+32/38>