Following up to a bug report against the 2.6.22 kernel, Andrew Morton and Linus Torvalds offered some tips on how to debug kernel problems. Andrew first pointed to netconsole.txt for instructions on setting up a netconsole, "when the machine has stalled, see if you can get a task trace with ALT-SYSRQ-t. This will require CONFIG_MAGIC_SYSRQ=y and possibly setting ignore_loglevel on the kernel boot command line."