用QEMU模拟调试裸机ARM64汇编，支持gdb单步调试

忘是亡心i 2022-09-04 06:44 275阅读 0赞

完全是方便自己查询，做个记录。

树莓派4的SOC是ARM64, cortex A72，支持最新的ARMv8指令集，且有众多的开源资料，适合用来学习ARM64汇编，其他芯片大同小异，遇到需要，再进一步研究qemu支持的芯片；

最新版官方qemu尚未支持树莓派4, 这里直接采用笨叔提供的qemu工具

# 1.测试代码test.S #

.global _start
    _start:
            mov x1,0x80000
            mov x3,16
    
            ldr x0,[x1]
            ldr x2, [x1,#8]
            ldr x4, [x1,x3]
            ldr x5, [x1,x3,lsl #3]

# 2. 编译 #

makefile文件

ARMGNU ?= aarch64-linux-gnu
    test.elf: test.o
            $(ARMGNU)-ld -Ttext 0x0  -o test.elf   $^
    %.o : %.S
            $(ARMGNU)-gcc  -o $@ $<  -g  -c
    clean:
            rm *.o *.elf    -f

# 3.qemu模拟调试 #

由于qemu自带gdb\_server，这里用gdb来单步调试

## 3.1 启动qemu ##

qemu-system-aarch64 -machine raspi4 -nographic -kernel test.elf -S -s

## 3.2 再开一个终端，启动gdb，链接qemu ##

gdb-multiarch --tui benos.elf

链接gdb\_server  
![\`\`\`bash(gdb) target remote localhost:1234Remote debugging using localhost:1234\_start () at test.S:3(gdb) b \_startBreakpoint 1 at 0x80000: file test.S, line 3.(gdb) c][bash_gdb_ target remote localhost_1234Remote debugging using localhost_1234_start _ at test.S_3_gdb_ b _startBreakpoint 1 at 0x80000_ file test.S_ line 3._gdb_ c]

\`\`  
查看寄存器值  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70]

## 3.3 用eclipse可视化环境调试 ##

(1).创建一个新工程test，添加带调试信息的程序test.elf，配置如下：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70 1]

链接成功后，启动gdb，可以方便查看寄存器或变量值如下：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70 2]

[bash_gdb_ target remote localhost_1234Remote debugging using localhost_1234_start _ at test.S_3_gdb_ b _startBreakpoint 1 at 0x80000_ file test.S_ line 3._gdb_ c]: /images/20220829/0a73934a8fe94a96bef12ff491fb8e43.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70]: /images/20220829/6f5b0e5dfa294a47a35019669c1bf2d3.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70 1]: /images/20220829/108fd7e564a542c5846424d201717339.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2x1dGVyZXNh_size_16_color_FFFFFF_t_70 2]: /images/20220829/16eb8211bfbb4039aecbadc66e883161.png