So at least the VIO servers started at the new FW level without problems, that's good news.
Is this partition the only one affected? Do other partitions boot?
If all partitions are affected it could make sense to reboot the VIO servers!
Can you login to the VIOS to check the errorlog there ("errlog -ls" or "errpt -a" after "oem_setup_env")?
I sometimes saw such stall conditions when there were lots of I/O errors. I had to remove the complete vhost (without unconfiguring it, fortunately) to then having it re-added by cfgdev.
The symptom of such conditions is usually "vhostx Virtual SCSI Host Adapter detected an error" in the errorlog
Steps to reconfigure the vhost - 1) rmdev -dev vhostx -ucfg -recursive 2) cfgdev -dev vhostx
vhostx is the affected SCSI host adapter (vhost0, vhost1, ...). -ucfg is very important, else the complete vhost config will be lost!
Sorry for the confusion with the HMC levels. I overlooked the first "7" in your post.
