A kernel debugger is a debugger present in some operating system kernels to ease debugging and kernel development by the kernel developers. A kernel debugger might be a stub implementing low-level operations, with a full-blown debugger such as GNU Debugger (gdb), running on another machine, sending commands to the stub over a serial line or a network connection, or it might provide a command line that can be used directly on the machine being debugged.
Operating systems and operating system kernels that contain a kernel debugger:
- The Windows NT family includes a kernel debugger named KD,[1] which can act as a local debugger with limited capabilities (reading and writing kernel memory, and setting breakpoints)[2] and can attach to a remote machine over a serial line, IEEE 1394 connection, USB 2.0 or USB 3.0 connection.[3] The WinDbg GUI debugger can also be used to debug kernels on local and remote machines.
- BeOS and Haiku include a kernel debugger usable with either an on-screen console or over a serial line. It features various commands to inspect memory, threads, and other kernel structures. In Haiku, the debugger is called "Kernel Debugging Land" (KDL).[4]
- DragonFly BSD
- Linux kernel; No kernel debugger was included in the mainline Linux tree prior to version 2.6.26-rc1 because Linus Torvalds didn't want a kernel debugger in the kernel.[5][6]
- NetBSD has DDB for local and KGDB for remote.
- macOS has ddb for local and kdp for remote.[11]
- OpenBSD includes ddb which has a syntax is similar to GNU Debugger.[12]
References
edit- ^ "Debugging Environments". Debugging Tools for Windows (WinDbg, KD, CDB, NTSD). Retrieved 16 February 2020.
- ^ "Local Kernel-Mode Debugging". Retrieved 16 February 2020.
- ^ "Live Kernel-Mode Debugging Using KD". Retrieved 16 January 2020.
- ^ "Welcome to Kernel Debugging Land".
- ^ "LWN.net". Retrieved 29 May 2008.
- ^ Torvalds, Linus (3 May 2008). "Linux 2.6.26-rc1". LWN. Retrieved 9 March 2015.
- ^ Nellitheertha, Hariprasad. "Inside the Linux kernel debugger". IBM. Archived from the original on 21 June 2008. Retrieved 29 May 2008.
- ^ "LWN Weekly Kernel News". 7 September 2008.
- ^ "MDB Github Website". 1 January 2016. Archived from the original on 22 March 2016.
- ^ "LWN Weekly Kernel News". 28 June 2010.
- ^ Singh, Amit (December 2003). "XNU: The Kernel". What is Mac OS X?. Archived from the original on 2 June 2020. Retrieved 25 May 2012.
the built-in low-level kernel debugger, ddb, is part of XNU's Mach component, and so is kdp, a remote kernel debugging protocol implementation
- ^ "ddb(4)". OpenBSD manual page server. 6 December 2019. Retrieved 13 December 2019.
The ddb debugger provides a means for debugging the kernel, and analysing the kernel after a system crash ("panic"), with a gdb(1)-like syntax.
