You have installed some patches, but now you get a kernel panic on reboot over and over again. You need to backout the offending patches, but you cannot get your system up-and-running in order to do that. Seems an impossible task? Not really!
I recently installed patches 118344-05 and 118844-20 on a Solaris 10/x86 system. All I got after that was a kernel panic on each reboot. So how do you backout such a patch?
First, try to boot your system from an alternative source. Several possibilities exist:
Next, mount the broken boot environment, e.g.
unix# mount /dev/dsk/c0d0s0 /mnt
Now you can backout the patch with "patchrm -R":
unix# patchrm -R /mnt 118844-20
unix# patchrm -R /mnt 118344-05
Now your system should be able to boot again...