blob: eb4fdc8b0bdb2f6f17171b44ce5a74d56d39e66d (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
title: Kernel compile "Hello world"
# Kernel compile "Hello world"
Compile minimal linux kernel module.
## Files
You need to create to files __Makefile__ and __hello_world.c__.
__Makefile__
```Makefile
obj-m += hello_world.o
KDIR ?= /lib/modules/$(shell uname -r)/build
all:
make -C $(KDIR) M=$(PWD) modules
clean:
make -C $(KDIR) M=$(PWD) clean
```
__hello_world.c__
```c
//http://www.tldp.org/LDP/lkmpg/2.4/html/c147.htm
#include <linux/module.h> /* Needed by all modules */
#include <linux/kernel.h>
int hello_world_init( void )
{
printk(KERN_DEBUG "Hello World!\n");
return 0;
}
void hello_world_exit( void )
{
printk(KERN_DEBUG "Exit Hello World!\n");
}
module_init( hello_world_init );
module_exit( hello_world_exit );
MODULE_LICENSE("GPL");
```
## Compile
Now if you havent done so ... install kernel headers of kernel that your system have now. And everything should be there.
```sh
make
```
## Load module
```sh
sudo insmod hello_world.ko
```
check that module is running
```sh
lsmod | grep hello
```
## Unload module
```sh
rmmod hello_world
```
### Install kernel headers raspbian
RaspberryPi4 ARMv8
```bash
sudo apt-get install raspberrypi-kernel-headers
```
|
