kernel debug（内核调试）

逃离我推掉我的手 2022-05-22 08:23 249阅读 0赞

1.yum -y install ncurses-devel.x86\_64 elfutils-libelf-devel.x86\_64 elfutils-libelf-devel.x86\_64  
  
2.download kernel and busybox  
  
3. kernel compress:

make ARCH=x86_64 CROSS_COMPILE=x86_64-none-linux- defconfig
       make ARCH=x86_64 CROSS_COMPILE=x86_64-none-linux- menuconfig
       make ARCH=x86_64 CROSS_COMPILE=x86_64-none-linux- -j8

4.Generate minimal initramfs

#!/usr/bin/bash
    ROOTFS=rootfs
    BUSYBOX=$(find busybox* -maxdepth 0 -type d)
    SYSROOT=$(x86_64-linux-gnu-gcc --print-sysroot)
    GLIBC_VERSION=$(${SYSROOT}/usr/bin/ldd --version | head -1 | cut -d' ' -f4)
    DYNAMIC_LIB_PATH_32=${SYSROOT}/lib
    DYNAMIC_LIB_PATH_64=${SYSROOT}/lib64
    
    rm -rf $ROOTFS
    mkdir -p ${ROOTFS}/{proc,sys,dev,etc,etc/init.d,lib,lib64,mnt,tmp,go}
    
    cat > $ROOTFS/etc/init.d/rcS <<EOF
    #!/bin/sh
    mount -t proc none /proc
    mount -t sysfs none /sys
    /sbin/mdev -s
    ifconfig lo up
    EOF
    
    chmod +x $ROOTFS/etc/init.d/rcS
    
    cat > $ROOTFS/etc/inittab <<EOF
    # /etc/inittab
    ::sysinit:/etc/init.d/rcS
    ::askfirst:-/bin/sh
    ::ctrlaltdel:/sbin/reboot
    ::shutdown:/bin/umount -a -r
    EOF
    
    chmod +x $ROOTFS/etc/inittab
    
    cp -rP ${BUSYBOX}/_install/* ${ROOTFS}
    
    cp -rP ${DYNAMIC_LIB_PATH_64}/libc-${GLIBC_VERSION}.so ${ROOTFS}/lib64/
    cp -rP ${DYNAMIC_LIB_PATH_64}/libc.so.6 ${ROOTFS}/lib64/
    
    cp -rP ${DYNAMIC_LIB_PATH_64}/libm-${GLIBC_VERSION}.so ${ROOTFS}/lib64/
    cp -rP ${DYNAMIC_LIB_PATH_64}/libm.so.6 ${ROOTFS}/lib64/
    
    cp -rP ${DYNAMIC_LIB_PATH_64}/librt-${GLIBC_VERSION}.so ${ROOTFS}/lib64/
    cp -rP ${DYNAMIC_LIB_PATH_64}/librt.so.1 ${ROOTFS}/lib64/
    
    cp -rP ${DYNAMIC_LIB_PATH_64}/libpthread-${GLIBC_VERSION}.so ${ROOTFS}/lib64/
    cp -rP ${DYNAMIC_LIB_PATH_64}/libpthread.so.0 ${ROOTFS}/lib64/
    
    cp -rP ${DYNAMIC_LIB_PATH_64}/ld-${GLIBC_VERSION}.so ${ROOTFS}/lib64/
    cp -rP ${DYNAMIC_LIB_PATH_64}/ld-linux-x86-64.so.2 ${ROOTFS}/lib64/
    
    cd ${ROOTFS}
    ln -sf bin/busybox init
    find . | cpio -o --format=newc > ../initramfs

$ cd ~/workspace 
    $ gdb
     (gdb) file linux-3.10.107/vmlinux 
    Reading symbols from /home/yeyuzhen/workspace/linux-3.10.107/vmlinux...done.
    (gdb) target remote:4321 
    Remote debugging using :4321 kgdb_breakpoint () at kernel/debug/debug_core.c:1014 1014 wmb(); /* Sync point after breakpoint */
    
    
    (gdb) b sys_sendto Breakpoint 1 at 0xffffffff815b44d0: file net/socket.c, line 1754. 
    (gdb) info b Num Type Disp Enb Address What 1 breakpoint keep y 0xffffffff815b44d0 in SyS_sendto at net/socket.c:1754 (gdb) c Continuing.