On reboot of a current amd64 kernel. running softraid crypto. (hand transcription)
syncing disks... done
kernel: protection fault trap, code=0
Stopped at bufq_destroy+0x83: mo
ddb{0}> tr
bufq_destroy() at bufq_destroy+0x83
sddetach()
config_detach()
scsi_detach_lun()
sr_discipline_shutdown()
sr_shutdown()
boot()
reboot()
sys_reboot()
