diff --git a/study/debug/tools/perf/kernel_modules/Makefile b/study/debug/tools/perf/kernel_modules/Makefile
new file mode 100644
index 0000000..0f6c6e4
--- /dev/null
+++ b/study/debug/tools/perf/kernel_modules/Makefile
@@ -0,0 +1,14 @@
+
+
+obj-m := test_kthread_run.o
+
+KERNELDIR ?= /lib/modules/$(shell uname -r)/build
+
+PWD := $(shell pwd)
+
+all:
+	make -C $(KERNELDIR) M=$(PWD) modules
+
+clean:
+	make -C $(KERNELDIR) M=$(PWD) clean
+
diff --git a/study/debug/tools/perf/kernel_modules/test_kthread_run.c b/study/debug/tools/perf/kernel_modules/test_kthread_run.c
new file mode 100644
index 0000000..9af5fd7
--- /dev/null
+++ b/study/debug/tools/perf/kernel_modules/test_kthread_run.c
@@ -0,0 +1,59 @@
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <linux/kthread.h>
+
+#include <linux/delay.h>  // error: implicit declaration of function ‘msleep’
+
+
+static struct task_struct *ptask;
+
+static int thread_function(void *data)
+{
+	int time_count = 0;
+	do
+	{
+		printk(KERN_INFO "thread_function: %d times", ++time_count);
+		msleep(1000);
+	}while(!kthread_should_stop()
+		&& time_count<=30);
+
+	return time_count;
+}
+
+static int test_kthread_run_init(void)
+{
+	int cpu = 1;
+
+	printk(KERN_INFO "test_kthread_run, world!\n");
+
+	ptask = kthread_run(thread_function, NULL, "mythread%d", cpu);
+	kthread_bind(ptask, cpu);
+
+	if (IS_ERR(ptask))
+	{
+		printk(KERN_INFO "create kthread failed!\n");
+	}
+	else
+	{
+		printk(KERN_INFO "create ktrhead ok!\n");
+	}
+
+	return 0;
+}
+
+static void test_kthread_run_exit(void)
+{
+	printk(KERN_INFO "test_kthread_run, exit!\n");
+
+	if (!IS_ERR(ptask))
+	{
+		int ret = kthread_stop(ptask);
+		printk(KERN_INFO "thread function has run %ds\n", ret);
+	}
+}
+
+module_exit(test_kthread_run_exit);
+module_init(test_kthread_run_init);
+MODULE_LICENSE("Dual BSD/GPL");
+
diff --git a/study/kernel/02-memory/00-code/layout/layout.c b/study/kernel/02-memory/00-code/layout/layout.c
index bc38b4d..32e3d2e 100644
--- a/study/kernel/02-memory/00-code/layout/layout.c
+++ b/study/kernel/02-memory/00-code/layout/layout.c
@@ -16,7 +16,7 @@ va 接收待查询的虚拟地址
 #include <linux/printk.h>
 #include <linux/memblock.h>
 #include <linux/kallsyms.h>
-
+#include <asm/fixmap.h>
 
 MODULE_LICENSE("GPL");
 
@@ -39,11 +39,8 @@ void show_layout(void)
 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 #define MLG(b, t) b, t, ((t) - (b)) >> 30
 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
-
+#if 0
 	pr_notice("Virtual kernel memory layout:\n");
-	pr_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM((unsigned long)phys_to_virt(SYMS_FUN("memblock_start_of_DRAM")),
-		    (unsigned long)high_memory));
 #ifdef CONFIG_KASAN
 	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
 		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
@@ -70,14 +67,17 @@ void show_layout(void)
 		MLM(PCI_IO_START, PCI_IO_END));
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
-		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
+		MLG(SYMS_VAL("vmemmap"), SYMS_VAL("vmemmap") + VMEMMAP_SIZE));
 	pr_notice("              0x%16lx - 0x%16lx   (%6ld MB actual)\n",
 		MLM((unsigned long)phys_to_page(SYMS_FUN("memblock_start_of_DRAM")),
 		    (unsigned long)virt_to_page(high_memory)));
 #endif
-
+	pr_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
+		MLM((unsigned long)phys_to_virt(SYMS_FUN("memblock_start_of_DRAM")),
+		    (unsigned long)high_memory));
+#endif
+	//pr_notice("KIMAGE_VADDR: 0x%16lx\n", KIMAGE_VADDR);
 	pr_notice("PAGE_OFFSET : 0x%16lx\n", PAGE_OFFSET);
-	pr_notice("KIMAGE_VADDR: 0x%16lx\n", KIMAGE_VADDR);
 #undef MLK
 #undef MLM
 #undef MLK_ROUNDUP
diff --git a/study/kernel/13-debug/0001-dump_backtrace/arm64/main b/study/kernel/13-debug/0001-dump_backtrace/arm64/main
new file mode 100755
index 0000000..df1e287
Binary files /dev/null and b/study/kernel/13-debug/0001-dump_backtrace/arm64/main differ
diff --git a/study/kernel/13-debug/0001-dump_backtrace/arm64/main.S b/study/kernel/13-debug/0001-dump_backtrace/arm64/main.S
new file mode 100644
index 0000000..e69de29
diff --git a/study/kernel/13-debug/0001-dump_backtrace/arm64/main.c b/study/kernel/13-debug/0001-dump_backtrace/arm64/main.c
new file mode 100644
index 0000000..a88fec9
--- /dev/null
+++ b/study/kernel/13-debug/0001-dump_backtrace/arm64/main.c
@@ -0,0 +1,35 @@
+#include <stdio.h>
+
+int func3(int a, int b)
+{
+	int c = a + b;
+	printf("c = %d\n", c);
+	return a + b;
+}
+
+int func2(int a)
+{
+	int b = 20;
+
+	b = func3(a, b);
+	printf("b = %d\n", b);
+
+	return b;
+}
+
+int func1(void)
+{
+	int a;
+
+	a = func2(10);
+	printf("a = %d\n", a);
+
+	return a;
+}
+
+int main(int argc, const char *argv[])
+{
+	func1();
+
+	return 0;
+}