xref: /linux/tools/testing/selftests/livepatch/test_modules/test_klp_mod_patch.c (revision 0fc8f6200d2313278fbf4539bbab74677c685531)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2026 Pablo Hugen <phugen@redhat.com>
3 
4 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
5 
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/livepatch.h>
9 #include <linux/seq_file.h>
10 
11 static int livepatch_mod_target_show(struct seq_file *m, void *v)
12 {
13 	seq_printf(m, "%s: %s\n", THIS_MODULE->name,
14 		   "this has been live patched");
15 	return 0;
16 }
17 
18 static struct klp_func funcs[] = {
19 	{
20 		.old_name = "test_klp_mod_target_show",
21 		.new_func = livepatch_mod_target_show,
22 	},
23 	{},
24 };
25 
26 static struct klp_object objs[] = {
27 	{
28 		.name = "test_klp_mod_target",
29 		.funcs = funcs,
30 	},
31 	{},
32 };
33 
34 static struct klp_patch patch = {
35 	.mod = THIS_MODULE,
36 	.objs = objs,
37 };
38 
39 static int test_klp_mod_patch_init(void)
40 {
41 	return klp_enable_patch(&patch);
42 }
43 
44 static void test_klp_mod_patch_exit(void)
45 {
46 }
47 
48 module_init(test_klp_mod_patch_init);
49 module_exit(test_klp_mod_patch_exit);
50 MODULE_LICENSE("GPL");
51 MODULE_INFO(livepatch, "Y");
52 MODULE_AUTHOR("Pablo Hugen <phugen@redhat.com>");
53 MODULE_DESCRIPTION("Livepatch test: patch for module-provided function");
54