View source for ERROR: /packages/ufs-file-system: Last Trap: Division by Zero

I've seen this a few times now, where I have applied the latest Recommended Patchset and get the following error on reboot:

  Boot device: /pci@0/pci@0/pci@2/scsi@0/disk@0,0:a  File and args: -v -mverbose
  -
  '''ERROR: /packages/ufs-file-system: Last Trap: Division by Zero'''
  
  {0} ok

You'll probably also see this beforehand, when you reboot the server after the patching:

   [root@biggus]$ reboot
   Jun 11 11:09:18 biggus reboot: rebooted by root
   updating /platform/sun4v/boot_archive
   Jun 11 11:09:51 biggus unix: /kernel/sys/sparcv9/kaio: undefined symbol
   Jun 11 11:09:51 biggus unix:  'aio_copyout_result_common'
   Jun 11 11:09:51 biggus unix: WARNING: mod_load: cannot load module 'kaio'
   Jun 11 11:09:51 biggus unix: /kernel/sys/sparcv9/kaio: undefined symbol
   Jun 11 11:09:51 biggus unix:  'aio_copyout_result_common'
   Jun 11 11:09:51 biggus unix: WARNING: mod_load: cannot load module 'kaio'
   Jun 11 11:09:52 biggus ufs: NOTICE: mount: not a UFS magic number (0xffffffff)

Before panic sets in, you need to do the following:

1. Boot the server off a CDROM or network 

2. Exit out of the installer so you get a basic command shell

3. Re-install the boot block on the boot disk

   installboot /usr/platform/`uname -i`/lib/fs/ufs/bootblk /dev/rdsk/c1t0d0s0

4. Update the boot archive.  

   mount -F ufs /dev/dsk/c1t0d0s0 /a
   bootadm update-archive -R /a

5. Reboot.