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1// SPDX-License-Identifier: GPL-2.02// Copyright (C) 2018 Joe Lawrence <joe.lawrence@redhat.com>3 4#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt5 6#include <linux/module.h>7#include <linux/kernel.h>8#include <linux/livepatch.h>9 10static int replace;11module_param(replace, int, 0644);12MODULE_PARM_DESC(replace, "replace (default=0)");13 14static const char *const module_state[] = {15 [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state",16 [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",17 [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",18 [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",19};20 21static void callback_info(const char *callback, struct klp_object *obj)22{23 if (obj->mod)24 pr_info("%s: %s -> %s\n", callback, obj->mod->name,25 module_state[obj->mod->state]);26 else27 pr_info("%s: vmlinux\n", callback);28}29 30/* Executed on object patching (ie, patch enablement) */31static int pre_patch_callback(struct klp_object *obj)32{33 callback_info(__func__, obj);34 return 0;35}36 37/* Executed on object unpatching (ie, patch disablement) */38static void post_patch_callback(struct klp_object *obj)39{40 callback_info(__func__, obj);41}42 43/* Executed on object unpatching (ie, patch disablement) */44static void pre_unpatch_callback(struct klp_object *obj)45{46 callback_info(__func__, obj);47}48 49/* Executed on object unpatching (ie, patch disablement) */50static void post_unpatch_callback(struct klp_object *obj)51{52 callback_info(__func__, obj);53}54 55static struct klp_func no_funcs[] = {56 { }57};58 59static struct klp_object objs[] = {60 {61 .name = NULL, /* vmlinux */62 .funcs = no_funcs,63 .callbacks = {64 .pre_patch = pre_patch_callback,65 .post_patch = post_patch_callback,66 .pre_unpatch = pre_unpatch_callback,67 .post_unpatch = post_unpatch_callback,68 },69 }, { }70};71 72static struct klp_patch patch = {73 .mod = THIS_MODULE,74 .objs = objs,75 /* set .replace in the init function below for demo purposes */76};77 78static int test_klp_callbacks_demo2_init(void)79{80 patch.replace = replace;81 return klp_enable_patch(&patch);82}83 84static void test_klp_callbacks_demo2_exit(void)85{86}87 88module_init(test_klp_callbacks_demo2_init);89module_exit(test_klp_callbacks_demo2_exit);90MODULE_LICENSE("GPL");91MODULE_INFO(livepatch, "Y");92MODULE_AUTHOR("Joe Lawrence <joe.lawrence@redhat.com>");93MODULE_DESCRIPTION("Livepatch test: livepatch demo2");94