无法使gdb在Qemu下运行的Linux内核中的断点处停止>

Question

已经编译了Linux 5.5.5内核，并通过make menuconfig添加了选项CONFIG_GDB_SCRIPTS并关闭了选项CONFIG_DEBUG_INFO_REDUCED。运行的qemu

qemu-system-x86_64 \
    -kernel arch/x86/boot/bzImage \
    -append "root=/dev/sda1" \
    -device virtio-scsi-pci,id=scsi0 \
  -drive file=../../zso2020_cow.qcow2,if=none,id=drive0 \
  -device scsi-hd,bus=scsi0.0,drive=drive0 \
  -enable-kvm \
  -smp 1 \
  -net nic,model=virtio -net user \
  -net user,hostfwd=tcp::2222-:22 \
  -m 1G -balloon virtio \
  -fsdev local,id=hshare,path=$(pwd),security_model=none -device virtio-9p-pci,fsdev=hshare,mount_tag=hshare \
  -chardev stdio,id=cons,signal=off -device virtio-serial-pci -device virtconsole,chardev=cons \
  -soundhw hda \
  -usb -device usb-mouse \
  -gdb tcp::23308 \
  -display none \
  -S

Qemu使用编译的内核运行，这是我在源代码中使用kprint检查过的内容。然后我就跑了

gdb \
    -ex "add-auto-load-safe-path $(pwd)" \
    -ex "file vmlinux" \
    -ex 'target remote localhost:23308' \
    -ex 'break start_kernel' \
    -ex 'continue'

（两个脚本都从具有编译内核的目录运行）

Qemu进入用户登录，并且gdb输出（等待断点）

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Reading symbols from vmlinux...done.
Remote debugging using localhost:23308
0x000000000000fff0 in exception_stacks ()
Breakpoint 1 at 0xffffffff8271db30: file init/main.c, line 577.
Continuing.

我也尝试过

• [hbr插入br

• 首先target remote :23308 i并设置断点，然后设置file vmlinux
• 转到已编译的内核目录并从qemu级别安装内核

在每种情况下，gdb都不会在断点处停止。

如何使用gdb正确连接到内核，在哪里查找错误？

已经编译了Linux 5.5.5内核，并通过make menuconfig添加了选项CONFIG_GDB_SCRIPTS并关闭了选项CONFIG_DEBUG_INFO_REDUCED。运行qemu qemu-system-x86_64 \ -kernel arch / x86 / boot / ...

Answer 1

解决该问题的方法是添加nokaslr选项并使用hbreak。那意味着替换