xref: /linux/lib/test_module.c (revision 5ac79730324c6f37106ce397586020ffe6e8e234)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This module emits "Hello, world" on printk when loaded.
4  *
5  * It is designed to be used for basic evaluation of the module loading
6  * subsystem (for example when validating module signing/verification). It
7  * lacks any extra dependencies, and will not normally be loaded by the
8  * system unless explicitly requested by name.
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/printk.h>
16 
17 static int __init test_module_init(void)
18 {
19 	pr_warn("Hello, world\n");
20 
21 	return 0;
22 }
23 
24 module_init(test_module_init);
25 
26 static void __exit test_module_exit(void)
27 {
28 	pr_warn("Goodbye\n");
29 }
30 
31 module_exit(test_module_exit);
32 
33 MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
34 MODULE_DESCRIPTION("module loading subsystem test module");
35 MODULE_LICENSE("GPL");
36