SGI Kernel Debugger - http://oss.sgi.com/projects/kdb kdb v1.2 is available for ix86 with patches against 2.3.99-pre2 and 2.4.0-test1. You need modutils >= 2.3.11 to use kdb v1.2. Most changes are internal, positioning kdb for different architectures. Users will see better symbol information, hardware and software breakpoints, more reliable SMP handling.