On Sep 22, 2006, at 4:36 PM, Kris Kennaway wrote:
Start by enabling INVARIANTS, INVARIANT_SUPPORT, DEBUG_LOCKS and DEBUG_VFS_LOCKS, then run 'show lockedvnods' and 'alltrace' in DDB (spammy, need that serial console), or at least trace the running processes (show allpcpu) and those listed in lockedvnods. Then call doadump and save the core+kernel.debug when you reboot.
Well, it happened again (as I was building the debugging kernel, no less)... but it only locked up one file system not the whole box. So my home dir was wedged, and everything trying to use anyone's home dir was wedged, but /usr and / were still responding.
So now I do have the kernel in place and the serial console is already there and your notes on what to do are there, so next time it happens I'm ready!