Research Of Linux Kernel's Software Debugging Technology

In recently years,with the rapid development of the embedded technology,the embedded products can be found everywhere and Linux has been increasingly used. The ARM chip with the features of low power consumption and high performance, can be widely adopted in embedded Linux products. In order to develop product and establish the system software platform, system kernel debugging is a key supporting technology.After analyzing various software methods and technologies of kernel debugging, a software method is given to debug the ARM Linux kernel, transplanting the KGDB which is a kernel debugging tool to complete. The hardware platform uses the Intel Xscale PXA255.The KGDB transplanting includes:KGDB's compilation and configuration which need modify the kernel's compile and configure files according the KGDB's functions and needs; the transplantation of initial module which realizes the communication module according the target board's hardware characteristics, including the driver of UART, network and the communication interface, provides a KGDB console which can print the information of kernel, takeovers the related exceptions of the Linux kernel according need; the transplantation of the KGDB's kernel function module which uses the method of undefined instructions according the ARM's features to solute the problem of how to make the Linux become in debug state, and then realizes the basic debug commands regulated in the GDB remote serial communication protocol which is the favorable guarantee of KGDB's powerful debugging function, and in order to complete debugging the kernel's module, gives several methods to get the effective address information when the module is loading。Through transplanting the KGDB, can realize the ARM Linux kernel's software debugging, and then support the Linux's transplantation.