kpatch/livepatch callback test patch:

  vmlinux
  pcspkr (mod)
  joydev (mod)

Note: update joydev's pre-patch callback to return -ENODEV to test failure path

--- src.old/fs/aio.c	2018-02-26 11:07:51.522610407 -0500
+++ src/fs/aio.c	2018-03-05 11:17:21.560015449 -0500
@@ -42,6 +42,50 @@
 #include <asm/kmap_types.h>
 #include <asm/uaccess.h>
 
+#include <linux/module.h>
+#include "kpatch-macros.h"
+
+static const char *const module_state[] = {
+	[MODULE_STATE_LIVE]	= "[MODULE_STATE_LIVE] Normal state",
+	[MODULE_STATE_COMING]	= "[MODULE_STATE_COMING] Full formed, running module_init",
+	[MODULE_STATE_GOING]	= "[MODULE_STATE_GOING] Going away",
+	[MODULE_STATE_UNFORMED]	= "[MODULE_STATE_UNFORMED] Still setting it up",
+};
+
+static void callback_info(const char *callback, patch_object *obj)
+{
+	if (obj->mod)
+		pr_info("%s: %s -> %s\n", callback, obj->mod->name,
+			module_state[obj->mod->state]);
+	else
+		pr_info("%s: vmlinux\n", callback);
+}
+
+static int pre_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+	return 0;
+}
+KPATCH_PRE_PATCH_CALLBACK(pre_patch_callback);
+
+static void post_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_PATCH_CALLBACK(post_patch_callback);
+
+static void pre_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_PRE_UNPATCH_CALLBACK(pre_unpatch_callback);
+
+static void post_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_UNPATCH_CALLBACK(post_unpatch_callback);
+
 #define AIO_RING_MAGIC			0xa10a10a1
 #define AIO_RING_COMPAT_FEATURES	1
 #define AIO_RING_INCOMPAT_FEATURES	0
--- src.old/drivers/input/joydev.c	2018-02-26 11:07:49.470610407 -0500
+++ src/drivers/input/joydev.c	2018-03-05 11:18:13.998015449 -0500
@@ -954,3 +954,47 @@ static void __exit joydev_exit(void)
 
 module_init(joydev_init);
 module_exit(joydev_exit);
+
+#include <linux/module.h>
+#include "kpatch-macros.h"
+
+static const char *const module_state[] = {
+	[MODULE_STATE_LIVE]	= "[MODULE_STATE_LIVE] Normal state",
+	[MODULE_STATE_COMING]	= "[MODULE_STATE_COMING] Full formed, running module_init",
+	[MODULE_STATE_GOING]	= "[MODULE_STATE_GOING] Going away",
+	[MODULE_STATE_UNFORMED]	= "[MODULE_STATE_UNFORMED] Still setting it up",
+};
+
+static void callback_info(const char *callback, patch_object *obj)
+{
+	if (obj->mod)
+		pr_info("%s: %s -> %s\n", callback, obj->mod->name,
+			module_state[obj->mod->state]);
+	else
+		pr_info("%s: vmlinux\n", callback);
+}
+
+static int pre_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+	return 0; /* return -ENODEV; */
+}
+KPATCH_PRE_PATCH_CALLBACK(pre_patch_callback);
+
+static void post_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_PATCH_CALLBACK(post_patch_callback);
+
+static void pre_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_PRE_UNPATCH_CALLBACK(pre_unpatch_callback);
+
+static void post_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_UNPATCH_CALLBACK(post_unpatch_callback);
--- src.old/drivers/input/misc/pcspkr.c	2018-02-26 11:07:49.477610407 -0500
+++ src/drivers/input/misc/pcspkr.c	2018-03-05 11:18:23.411015449 -0500
@@ -136,3 +136,46 @@ static struct platform_driver pcspkr_pla
 };
 module_platform_driver(pcspkr_platform_driver);
 
+#include <linux/module.h>
+#include "kpatch-macros.h"
+
+static const char *const module_state[] = {
+	[MODULE_STATE_LIVE]	= "[MODULE_STATE_LIVE] Normal state",
+	[MODULE_STATE_COMING]	= "[MODULE_STATE_COMING] Full formed, running module_init",
+	[MODULE_STATE_GOING]	= "[MODULE_STATE_GOING] Going away",
+	[MODULE_STATE_UNFORMED]	= "[MODULE_STATE_UNFORMED] Still setting it up",
+};
+
+static void callback_info(const char *callback, patch_object *obj)
+{
+	if (obj->mod)
+		pr_info("%s: %s -> %s\n", callback, obj->mod->name,
+			module_state[obj->mod->state]);
+	else
+		pr_info("%s: vmlinux\n", callback);
+}
+
+static int pre_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+	return 0;
+}
+KPATCH_PRE_PATCH_CALLBACK(pre_patch_callback);
+
+static void post_patch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_PATCH_CALLBACK(post_patch_callback);
+
+static void pre_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_PRE_UNPATCH_CALLBACK(pre_unpatch_callback);
+
+static void post_unpatch_callback(patch_object *obj)
+{
+	callback_info(__func__, obj);
+}
+KPATCH_POST_UNPATCH_CALLBACK(post_unpatch_callback);