panic: ffs_blkfree: freeing free block

[Randy Bush]

> Hmm, after running fsck a few times to make sure all my file systems
> were in top condition, the panic has yet to occur.  <crossing fingers>

i think you need goat and chicken entrails to go with the crossed
fingers.  i fscked three times in single user, booted multi, did
    portupgrade -rf -o emulators/linux_base-8 emulators/linux_base
and had the 
    handle_written_inodeblock: live inodedep
panic within two minutes

randy