Android Deep Explore tenth chapter

The Android emulator can only use the Kgdbserver debugger through port mapping. However, the Development Board can be connected via the serial port in addition to the IP connection to the Kgdbserver. The Development Board also has the Kgdbserver program, which can be run directly.

Most developers think of KGDB as the best kernel debugging tool. In addition to providing a similar log output function for the PRINTK function, KGDB allows developers to link target devices directly on the PC via GDB. KGDB contains two parts: the KGDB kernel and a set of connection interfaces. These interfaces currently support serial TTY device connections and Ethernet connections. The serial port connection needs to specify the serial port TTY device to be connected through the kernel parameter KGDBOC, and the Ethernet connection specifies the IP and port number through the kernel parameter Kgdboc. The KGDB supports a variety of processor architectures. Because of the large differences in these processor architectures, KGDB implements the KGDB core separately for each supported processor architecture, such as the KGDB core source code file for the ARM architecture ARCH/ARMKERNEL/KGDB.C.

Linux kernel debugging has been considered by many people to be very difficult. Most people prefer to use the PRINTK function to output debug information directly, and are reluctant to debug with various commands (GDB, gdbserver, KGDB, etc.). Because doing so does not necessarily make for more benefits. When you find that a piece of code has too many bugs or is difficult to printk function output information, consider using KGDB to position the bug in step by step.

Android Deep Explore tenth chapter