init && exit

source/module/Makefile_bak

@@ -1,3 +0,0 @@
-KMOD = variable_monitor
-obj-m := $(KMOD).o
-$(KMOD)-objs := monitor_kernel.o

source/module/monitor_kallsyms.c

@@ -17,7 +17,7 @@ int (*orig_kernfs_name)(struct kernfs_node *kn, char *buf, size_t buflen);
 int (*orig_access_remote_vm)(struct mm_struct *mm, unsigned long addr,
                              void *buf, int len, unsigned int gup_flags);
 
-/// @brief init kallsyms_lookup_name
+/// @brief init kallsyms_lookup_name,all orig_fun are depend on it
 /// @param
 /// @return 0 is success
 static int fn_kallsyms_lookup_name_init(void) {
@@ -25,7 +25,7 @@ static int fn_kallsyms_lookup_name_init(void) {
   diag_kallsyms_lookup_name = (void *)kprobe_kallsyms_lookup_name.addr;
   unregister_kprobe(&kprobe_kallsyms_lookup_name);
 
-  printk("xby-debug, diag_kallsyms_lookup_name is %p\n",
+  printk(KERN_INFO "diag_kallsyms_lookup_name is %p\n",
          diag_kallsyms_lookup_name);
 
   if (!diag_kallsyms_lookup_name) {
@@ -33,15 +33,27 @@ static int fn_kallsyms_lookup_name_init(void) {
   }
   return 0;
 }
-
+/**
+ * @brief get all orig_fun
+ *
+ * @return int 0 is success
+ */
 int init_orig_fun(void) {
-  fn_kallsyms_lookup_name_init();    // init kallsyms_lookup_name
+  int ret = fn_kallsyms_lookup_name_init();  // init kallsyms_lookup_name
+
+  if (ret)
+  {
+    printk(KERN_INFO "init kallsyms_lookup_name failed\n");
+    return ret;
+  }
+
   LOOKUP_SYMS(stack_trace_save_tsk);  // stack_trace_save_tsk
   LOOKUP_SYMS(show_stack);            // show_stack
   LOOKUP_SYMS(idle_sched_class);      // idle_sched_class
   LOOKUP_SYMS(access_remote_vm);      // access_remote_vm
 
-  LOOKUP_SYMS_NORET(get_task_type); // get_task_type
+  LOOKUP_SYMS_NORET(
+      get_task_type);  // get_task_type | this fun is not available on 5.17.15
   LOOKUP_SYMS_NORET(kernfs_name);  // kernfs_name
   return 0;
 }

source/module/monitor_kernel.c

@@ -64,7 +64,7 @@ static struct file_operations fops = {
 };
 
 int init_module(void) {
-  printk(KERN_INFO "%s\n", __FUNCTION__);
+  printk(KERN_INFO "variable_monitor fun: %s\n", __FUNCTION__);
   if (alloc_chrdev_region(&dev_num, 0, 1, DEVICE_NAME) < 0) {
     printk(KERN_ALERT "Failed to register device number\n");
     return -1;
@@ -110,7 +110,7 @@ int init_module(void) {
 }
 
 void cleanup_module(void) {
-  printk(KERN_INFO "%s\n", __FUNCTION__);
+  printk(KERN_INFO "variable_monitor fun: %s\n", __FUNCTION__);
   // clear all watch | free buffer
   monitor_exit();
 

source/module/monitor_kernel_lib.c

@@ -56,10 +56,10 @@ static void clear_all_watch(void) {
 int monitor_init(void) {
   int ret = 0;
 
-  init_orig_fun();                     // init orig_X
+  ret = init_orig_fun();  // init orig_X
+  if (ret) return ret;
   ret = init_buffer(50 * 1024 * 1024);  // 50M
-  if (ret)
-    return 0;
+  if (ret) return -1;
   return 0;
 }
 
@@ -72,6 +72,7 @@ void monitor_exit() {
   clear_all_watch();
   // free buffer
   destroy_diag_variant_buffer(&load_monitor_variant_buffer);
+  printk(KERN_INFO "clear all buffer\n");
 }
 /**
  * @brief start watch variable

source/module/monitor_timer.c

@@ -200,5 +200,5 @@ void cancel_all_hrTimer(void) {
     TIMER_CANCEL(timer);
   }
 
-  printk("HrTimer cancel,module keep %d hrtimer for now\n", kernel_wtimer_num);
+  printk(KERN_INFO "HrTimer cancel,module keep %d hrtimer for now\n", kernel_wtimer_num);
 }